The Bench Grafter's Handbook Principles & Practice

Containing 500 full color photographs and illustrations, The Bench Grafter?s Handbook: Principles and Practice presents exhaustive information on all aspects of bench grafting. It details requirements of more than 200 temperate woody plant genera, covering over 2,000 species and cultivars including important ornamental, temperate fruit, and nut crops. The book explains the principles and practices of bench grafting, new procedures to enhance grafting success, and recommendations for further scientific investigation.

Practical issues to aid professionals and the beginner, include detailed accounts, supported by pictures and diagrams, of the main grafting methods, knifesmanship techniques, and methods of training. Provision and design, now and for the future, of suitable structures, grafting facilities, and equipment, to provide ideal controlled environments for grafts, are described.

The book describes major grafting systems, sub-cold, cold, warm, supported warm, hot-pipe, and other grafting strategies. It provides details of health and safety issues; work stations, seat design, lighting levels; recorded output figures for various types of graft; grafting knives and tools; and methods of sharpening by hand and machine.

Features:

• Comprehensive description, pictures, and diagrams of how to learn and utilize important grafting methods.
• Detailed information and scientific principles behind the selection, specification, and choice of the main graft components ? the rootstock and scion.
• Scientific principles and practicalities of providing optimal plant material, equipment, facilities and environmental conditions for graft union development including addressing the problems of graft incompatibility.
• Discussion of the actual and potential role of bench grafting in woody plant conservation with suggestions for new initiatives.

This book is intended for use by nurserymen; those involved in the upkeep of extensive plant collections; conservationists; plant scientists; lecturers in horticulture; horticultural students; and amateurs with an interest in grafting.

Contents

Preface...........................................................................................................................................xxix

Acknowledgements..................................................................................................................... xxxiii

Author.........................................................................................................................................xxxvii

Introduction..................................................................................................................................xxxix

PART ONE Bench Grafting in Practice

Chapter 1 Grafting in Nature and in the Hands of the Grafter......................................................3

Vascular Continuity.......................................................................................................3

Chapter 2 Grafting Strategies: Categorisation of Grafting Methods.............................................7

Grafting Strategies........................................................................................................7

Apical Grafting.........................................................................................................7

Side Grafting............................................................................................................7

Apical and Side Grafting Strategies Compared............................................................8

Speed........................................................................................................................8

Space Requirements.................................................................................................8

Growth and Survival................................................................................................8

Convenience.............................................................................................................8

Heading-Back: A Specific Requirement of Side Grafts...........................................9

Grafting: The Five Basic Methods.............................................................................. 11

Splice Grafts........................................................................................................... 11

Veneer Grafts.......................................................................................................... 12

Wedge Grafts.......................................................................................................... 12

Inlay Grafts............................................................................................................. 13

Rind Grafts............................................................................................................. 13

The Three Categories of Importance to Bench Grafters............................................ 14

Apical Veneer, Splice and Wedge Grafts Compared.................................................. 15

Machine and Tool-Made Grafts.................................................................................. 16

Chapter 3 Making the Graft......................................................................................................... 19

The Basics................................................................................................................... 19

Understanding Stem and Root Cambia.................................................................. 19

Importance of Good Knifesmanship...................................................................... 19

Preparation of Components Prior to Grafting................................................... 19

Holding the Knife – Support and Control......................................................... 19

Splice Grafts................................................................................................................ 21

Splice Grafting Methods........................................................................................ 21

Alternative Splice Grafting Method..................................................................24

Whip and Tongue Graft..........................................................................................27

Whip and Tongue Grafting Methods.................................................................27

Veneer Grafts..............................................................................................................28

Apical Veneer Grafts..............................................................................................29

Short Tongue Apical Veneer (Apical Veneer)....................................................29

Long Tongue Apical Veneer (Modified Apical Veneer)....................................29

Side Veneer Grafts..................................................................................................30

Short Tongue Side Veneer (Side Veneer)........................................................... 31

Long Tongue Side Veneer (Modified Side Veneer)........................................... 31

Side Sloping Veneer........................................................................................... 31

Veneer Grafting Methods....................................................................................... 33

Sequence of Cuts for Veneer Grafts.................................................................. 33

Cambial Alignment for Veneer Grafts..............................................................38

Wedge Grafts...............................................................................................................40

Apical Wedge Graft................................................................................................40

Rootstock Cuts for Wedge Grafts...................................................................... 41

Scion Cuts for Wedge Grafts............................................................................. 41

Cambial Alignment for Wedge Grafts................................................................... 42

Side Wedge Graft................................................................................................... 42

Chapter 4 Fine Tuning Grafting: Positioning; Sequences; Training; Rates of Work.................. 43

Positioning Grafts........................................................................................................ 43

Height above Root Collar or Soil Level................................................................. 43

Rootstock and Scion Placement – Stimulant Bud – Grafting Methods................. 43

Priority – Scion or Rootstock?.................................................................................... 45

Sequence of Actions for Performing the Graft........................................................... 47

Training and Practice.................................................................................................. 47

Rates of Work..............................................................................................................49

Chapter 5 Grafting Knives: Grafting Machines and Tools.......................................................... 51

Knife Selection............................................................................................................ 51

Folding Blade Knives............................................................................................. 51

Design and Construction................................................................................... 51

Folding Blade Models............................................................................................. 52

Fixed Blade Knives................................................................................................54

Disposable Blade Knives........................................................................................54

Knife Sharpening........................................................................................................ 55

Hand Sharpening – Equipment and Materials....................................................... 55

Choice of Cutting Edge Angle...........................................................................56

Stone Choice and Maintenance of Sharpening Stones......................................56

Procedures.........................................................................................................56

Techniques for Curved (Hooked) Blades.......................................................... 57

Stages in Sharpening – Burr Removal – Honing................................................... 58

Honing............................................................................................................... 58

Stropping............................................................................................................ 58

Cutting Edge Retention..................................................................................... 59

Key Points for Effective Hand Sharpening............................................................ 59

Machine and Machine‑Aided Knife Sharpening...................................................60

Sharpening Aids................................................................................................60

Sharpening Machines........................................................................................60

Testing for Sharpness.............................................................................................60

Knife Maintenance.................................................................................................60

Grafting Machines and Grafting Tools....................................................................... 61

Grafting Machines.................................................................................................. 61

Grafting Tools........................................................................................................63

Chapter 6 Ties – Tying and Sealing.............................................................................................65

Basic Principles...........................................................................................................65

Tying Materials...........................................................................................................65

Non-Enclosing and Enclosing Ties.............................................................................66

Non-Enclosing Ties................................................................................................66

Tying-In Procedures and Techniques for Non-Enclosing Ties.......................... 67

Tying-Off........................................................................................................... 70

Enclosing Ties........................................................................................................ 71

Tying Procedures for Enclosing Ties................................................................. 71

Self-Adhesive Enclosing Ties................................................................................. 72

Mechanised Tying-In......................................................................................... 72

Alternative Graft Fixing Methods............................................................................... 73

Sealants and Waxes..................................................................................................... 74

Hot Sealants............................................................................................................ 74

Melting Hot Waxes............................................................................................ 75

Cold Sealants.......................................................................................................... 75

Application Methods.............................................................................................. 76

Brush Application.............................................................................................. 76

Dipping.............................................................................................................. 76

Chapter 7 Work Station: Equipment and Associated Ancillary and Safety Equipment............. 79

Centralised, Integral or Mobile Workstations............................................................. 79

Work Station – Logistics of Handling Grafts and Rootstocks............................... 79

Work Station Equipment.............................................................................................80

The Grafting Bench.....................................................................................................80

Height Adjustment Related to Seating and Method............................................... 81

Layout and Handling..............................................................................................82

Grafting Procedures and Bench Design.................................................................82

Seating.........................................................................................................................82

Seat and Bench Placement......................................................................................82

Lighting.......................................................................................................................83

Ancillary Equipment and Activities – Safety Equipment...........................................83

Secateurs.................................................................................................................84

Bench and Plant Material Cleanliness...................................................................84

Knife Blade Cleaning and Sterilisation..................................................................84

Inspecting Grafts....................................................................................................85

Labelling and Marking...........................................................................................85

Protective Clothing.................................................................................................86

Production Planning, Computers and Recording Data...............................................86

First Aid Equipment, Health and Safety and Risk Assessments................................87

Risk Assessments...................................................................................................88

PART TWO The Graft Components – Rootstock and Scion

Chapter 8 Rootstocks: Origin and Underlying Principles of Anatomy and Physiology.............. 91

Origin.......................................................................................................................... 91

Seedlings................................................................................................................ 91

Clonal.....................................................................................................................92

Roots or Root Systems............................................................................................92

Unrooted Stems......................................................................................................93

Size of Rootstock.........................................................................................................94

Root Pressure (Bleeding) and Root Activity...............................................................94

Chapter 9 Rootstocks: Categories; Acquisition; Specifications; Culture.....................................97

Categories of Rootstocks.............................................................................................97

Acquisition..................................................................................................................97

Bought-In Rootstocks.............................................................................................97

In-House Production...............................................................................................98

Rootstock Specifications – Terms Used......................................................................98

Bare-Root Deciduous Rootstocks...............................................................................99

Specifications to Meet Requirements.....................................................................99

Transport – Reception and Handling.....................................................................99

Preparation for Immediate Use..............................................................................99

Storage (Short- or Long-Term).............................................................................. 100

Bare-Root Evergreen Rootstocks.............................................................................. 100

Requirements – Specifications............................................................................. 100

Transport – Reception and Handling................................................................... 100

Storage.................................................................................................................. 101

Root-Balled Rootstocks............................................................................................. 101

Rootstocks for Top-Working..................................................................................... 101

Rootstocks for Cuttings-Grafts................................................................................. 101

Potted Rootstocks – Sourced from Other Producers................................................ 102

Requirements – Specifications............................................................................. 102

Transport and Handling........................................................................................ 102

Reception for Grafting Shortly after Arrival....................................................... 102

Reception for Use at a Later Date........................................................................ 102

Potted Rootstocks – Produced In-House................................................................... 102

Specifications........................................................................................................ 103

Pot Sizes and Types.............................................................................................. 103

Plug Grown................................................................................................................ 104

Specification and Types........................................................................................ 104

Requirements and Handling................................................................................. 104

Rootstock Culture – Bare-Root................................................................................. 105

Soil – Sowing – Seedling Density........................................................................ 105

Herbicides for Rootstocks Growing in the Field.................................................. 105

Rootstock Culture – Pot Grown................................................................................ 105

Establishment....................................................................................................... 105

Potting Composts................................................................................................. 106

Growing Conditions............................................................................................. 106

Weed Control Strategies....................................................................................... 107

Pesticide Use......................................................................................................... 108

Drying-Off Pot Grown Rootstocks........................................................................... 108

Chapter 10 Scions – General Principles – Acquisition – Stock Mother Plants – Selection

and Collection........................................................................................................... 111

Scions and Cuttings Compared................................................................................. 111

Principles for Selection of Scion Wood..................................................................... 111

Differences between ‘Ripe’ and ‘Unripe’ Shoots................................................ 112

Scion Acquisition – Non-Commercial Sources........................................................ 113

Plant Collections................................................................................................... 113

Scion Acquisition – Commercial Suppliers.............................................................. 114

Other Nurserymen or Specialist Suppliers........................................................... 114

Overseas Sources.................................................................................................. 114

High Health Status Material................................................................................. 115

Scion Acquisition from Internal Sources.................................................................. 116

Scions from Growing on Stock............................................................................ 116

Scions from Dedicated Container Grown Mother Plants..................................... 116

Scions from Stock Mother Plant Beds.................................................................. 117

Strategic Advantages....................................................................................... 117

Technical Advantages...................................................................................... 117

Disadvantages.................................................................................................. 118

Yield of Scion Material from Stock Mother Plant Beds...................................... 118

Establishment and Maintenance of Stock Beds........................................................ 119

Site and Soil – Initial Assessments....................................................................... 119

Soil Preparation.................................................................................................... 119

Planting Procedures and Design.......................................................................... 120

Weed Control........................................................................................................ 120

Pesticide and Fungicide Application.................................................................... 121

Pruning and Training Stock Mother Plants.............................................................. 121

Deciduous Trees................................................................................................... 121

Deciduous Shrubs................................................................................................. 122

Evergreen Trees and Shrubs................................................................................. 123

Conifers................................................................................................................ 123

Upright Formal Shaped Conifers..................................................................... 123

Upright Informal Shaped Conifers..................................................................124

Spreading and Dwarf Conifers........................................................................124

Climbers...............................................................................................................124

Scions for Winter Grafts...........................................................................................124

Deciduous Hardwoods..........................................................................................124

Collection.........................................................................................................124

Storage............................................................................................................. 125

Preparation....................................................................................................... 126

Evergreen Hardwoods Scions............................................................................... 126

Collection......................................................................................................... 126

Storage – Preparation....................................................................................... 127

Scions for Summer Grafts......................................................................................... 127

Summer Dormant Deciduous and Evergreen....................................................... 127

Collection......................................................................................................... 127

Storage............................................................................................................. 127

Preparation....................................................................................................... 127

Summer Active Deciduous and Evergreen........................................................... 128

Collection......................................................................................................... 128

Storage............................................................................................................. 129

Preparation....................................................................................................... 129

Conifer Scions........................................................................................................... 129

Handling/Preparation for Conifer Scions............................................................. 129

Storage............................................................................................................. 130

Transport of Scion Material...................................................................................... 130

Post Grafting Scion Growth – Use of Bud Growth Stimulants................................ 130

PART THREE Achieving the Union

Chapter 11 Anatomy and Physiology of Graft Union Formation and Development................... 135

Basic Woody Plant Anatomy.................................................................................... 135

Woody Plant – Primary Stem Anatomy............................................................... 135

Woody Plant – Secondary Stem Anatomy........................................................... 136

Woody Plant Anatomy – Vascular System........................................................... 137

Graft Union Formation.............................................................................................. 138

Union Formation – Response to Wounding......................................................... 138

Stages in the Formation of the Graft Union......................................................... 139

First Stage – Necrotic Plate............................................................................. 139

Second Stage.................................................................................................... 140

Third Stage...................................................................................................... 140

Fourth Stage..................................................................................................... 141

Diagrammatic Representation of Graft Union Formation................................... 142

Factors Influencing Callus Development.................................................................. 144

Genetic Influence.................................................................................................. 144

Rootstock – Scion – Grafting Method.................................................................. 144

Temperature.......................................................................................................... 144

Rootstock Activity, Root Extension...................................................................... 146

Moisture, Humidity, Oxygen – Effects of Sealing............................................... 146

Timing/Seasonal Patterns/Pruning...................................................................... 147

Polarity................................................................................................................. 148

Stimulant Buds..................................................................................................... 148

Root Pressure (Bleeding)...................................................................................... 149

Genetic Variability........................................................................................... 152

Stage of Growth – Timing............................................................................... 154

Root Temperature............................................................................................ 154

Substrate Moisture........................................................................................... 154

Side Graft, Height of Graft.............................................................................. 154

Graft Hybrids............................................................................................................ 154

Rootstock and Scion Interactions.............................................................................. 156

Chapter 12 Compatibility............................................................................................................. 159

Recognising Incompatibility..................................................................................... 159

Causes of Incompatibility......................................................................................... 159

Predicting Compatibility........................................................................................... 162

Future Progress – Strategies to Overcome Incompatibility...................................... 163

Double-Working................................................................................................... 164

Proven Inter-Stems.......................................................................................... 164

Unproven Inter-Stems...................................................................................... 165

Other Strategies to Overcome Incompatibility..................................................... 167

Hybrid Seedlings............................................................................................. 167

Root Grafting................................................................................................... 169

Chapter 13 Graft Environment for Graft Union Development.................................................... 171

Water Exchange and Loss between the Plant and the Atmosphere.......................... 171

Humidity – The Enclosed (Supportive) Environment.......................................... 172

Water – Practical Methods of Preventing Water Loss in Grafts.......................... 173

Rootstocks........................................................................................................ 173

Preventing Water Loss from Grafts using Dormant Leafless Scions.............. 173

Preventing Water Loss from Grafts using Leafy and De-Leaved Scions....... 174

High Humidity Combined with Sealing.......................................................... 174

Temperature – The Graft Environment..................................................................... 174

Additional Heat.................................................................................................... 174

Shading................................................................................................................. 175

Shading in High Humidity (Enclosed) Environments......................................... 175

Shade Level Calculations................................................................................. 177

Ventilation – Temperature and Humidity Control.................................................... 177

Macro-Ventilation................................................................................................. 177

Micro-Ventilation................................................................................................. 178

Setting-Up and Management of the Enclosed Environment..................................... 178

Bed Design........................................................................................................... 178

Bed Layout – Condensation.................................................................................. 179

Moisture Level and Temperature of Standing Down Substrate........................... 179

Cover Materials.................................................................................................... 179

Anti-Condensation Strategies............................................................................... 180

Management of the Environment within Walk-In Structures.............................. 183

Monitoring Grafts during Union Formation............................................................. 184

Graft Treatments....................................................................................................... 184

Influencing Union Development........................................................................... 184

Disease Suppression............................................................................................. 185

Cold Storage Post-Graft Union Formation................................................................ 185

PART FOUR Facilities: Structures and Equipment

Chapter 14 Protected Structures – High Humidity Enclosures – Shading Materials.................. 189

Glasshouses............................................................................................................... 189

Walk-In Enclosed Structures within a Glasshouse or Polytunnel........................ 190

Polytunnels................................................................................................................ 190

Free-Standing, Walk-In Grafting Polytunnels.......................................................... 191

Poly-Tent.................................................................................................................... 192

Holding Tent.............................................................................................................. 192

Shading – External.................................................................................................... 194

Natural Shade....................................................................................................... 194

Shade Hall............................................................................................................ 194

Additional External Hoops................................................................................... 195

Direct Application................................................................................................ 195

Shading – Internal/External...................................................................................... 195

Shading Screens................................................................................................... 196

Chapter 15 Ground Level Beds – Benches – Heating – Humidification..................................... 197

Ground Level Beds within Greenhouses.................................................................. 197

Ground Level Beds for Cold or Warm Callusing................................................. 197

Warm Callusing – Provision of Heat for Ground Level Beds.............................. 197

Electricity........................................................................................................ 197

Hot Water......................................................................................................... 198

Providing Bottom Heat and Space Heating..................................................... 199

Grafting Beds.................................................................................................. 199

Bottom Heat throughout the Entire Floor........................................................200

Grafts Housed on Benches........................................................................................ 201

Bench Heating Systems........................................................................................202

Thermostats...............................................................................................................202

Thermostats – Electro-Mechanical......................................................................202

Thermostats – Digital (Electronic).......................................................................202

Humidification...........................................................................................................202

Chapter 16 Hot-Pipe Facilities: Design and Construction...........................................................205

Hot-Pipe – Heat Source.............................................................................................205

Electricity.............................................................................................................205

Hot Water..............................................................................................................206

The Heating Chamber...............................................................................................206

Slotted Cover........................................................................................................206

Layered Slotted Cover.....................................................................................208

Solid Cover (‘Sandwiched’ Cover).......................................................................208

Extruded Polystyrene Sheets Fabricated to Shape..........................................208

Half-Round Plastic Rainwater Gutters............................................................209

Square Section Rainwater Gutters................................................................... 211

Plywood or Insulating Boards Fabricated to Shape........................................ 211

Hot-Pipe – Stacked Assemblies............................................................................ 211

Separate Assembly Stacking........................................................................... 211

Integrated Assembly Stacking......................................................................... 212

Alternative Design for Aligned Chambers................................................................ 214

‘Economy’ Design..................................................................................................... 214

Summer Storage........................................................................................................ 215

Temperature Control for Hot-Pipe Systems.............................................................. 215

Chapter 17 Growth Chambers for Grafts.................................................................................... 217

PART FIVE Grafting Systems

Chapter 18 Features and Management of Different Grafting Systems....................................... 221

Sub-Cold Callusing (Hibernation Callusing)............................................................ 221

Cold Callusing – For Deciduous Species..................................................................222

Bare-Root Rootstocks...........................................................................................222

Potted Rootstocks.................................................................................................223

Modified Cold Callusing...........................................................................................224

Warm Callusing.........................................................................................................224

Dormant Hardwood Species.................................................................................225

Deciduous Hardwoods in Summer Dormancy.....................................................225

Deciduous Hardwood Species in Active Growth (Early/Mid-Summer

Grafting)...............................................................................................................226

Dormant Evergreen Hardwoods...........................................................................226

Summer Dormant Evergreen Hardwoods............................................................226

Summer Active Evergreen Hardwoods................................................................227

Supported Warm Callusing Systems.........................................................................228

Conifer Grafting........................................................................................................228

Deciduous Conifers..............................................................................................229

Evergreen Conifers...............................................................................................229

Pinaceae and Sciadopityaceae.........................................................................229

Cupressaceae...................................................................................................230

Aurucariaceae, Podocarpaceae and Taxaceae................................................. 231

Summer Dormant Conifers.................................................................................. 231

Hot-Pipe (Hot Callusing) – Horticultural Management – Plant Material................. 231

Output and Capacity............................................................................................. 233

Rootstocks............................................................................................................ 233

Grafting Methods.................................................................................................234

Temperature and Timing...................................................................................... 235

Cold Storage Post-Graft Union Formation...........................................................236

Top-Working..............................................................................................................236

Frame-Working......................................................................................................... 239

Enhanced Scion Production......................................................................................240

Double-Working........................................................................................................240

Multi-Grafts..............................................................................................................240

Root Grafting............................................................................................................242

Source, Specifications and Storage.......................................................................242

Grafting Methods and Tying-In............................................................................244

Aftercare...............................................................................................................245

Nurse Grafting..........................................................................................................245

Nurse-Seed Grafting.................................................................................................246

Grafting Method...................................................................................................246

Aftercare.......................................................................................................... 247

Cuttings-Grafts.......................................................................................................... 247

Pre-Formed Roots................................................................................................ 247

Unrooted Stems....................................................................................................248

“Long John” Grafts...................................................................................................249

Approach Grafting; Grafting with Attached Scions.................................................250

Deciding upon the Best Grafting Strategy, Method and System..............................250

Small Grafting Unit Concerned with Species Diversity......................................250

Large, Specialised Grafting Unit Concerned with High Output.......................... 251

PART SIX Role of Grafting in Conservation

Chapter 19 Conservation.............................................................................................................. 255

Conservation of Plants in Cultivation (Ex Situ)........................................................ 255

Conservation of Plants in the Wild (In Situ)............................................................. 255

Propagation for Conservation....................................................................................256

Attributes of Grafting for Conservation............................................................... 257

Genetic Integrity; Diversity; Selection............................................................ 257

Transport – Plant Health.................................................................................. 257

Successful Outcomes – Rejuvenation.............................................................. 257

Output.............................................................................................................. 258

Speed of Response........................................................................................... 258

Facility Requirements...................................................................................... 258

Technical Input – Artisan Involvement – Skills Transfer................................ 258

Practical Applications for Grafting in Conservation............................................ 258

Recovery of Endangered Species from the Wild............................................. 258

Recovery of Juvenility..................................................................................... 259

Retention of Genetic Integrity......................................................................... 259

Speed and Quantity of Production................................................................... 259

Need for Rapid Response................................................................................ 259

Rootstock Selection to Overcome Environmental Challenges........................260

Grafting Potential for Red List Species....................................................................260

Setting Up a Grafting Facility................................................................................... 261

The Future of Grafting in Conservation................................................................... 261

PART SEVEN Genera Specific Requirements

Introduction.....................................................................................................................................265

Chapter 20 Abies (Pinaceae) – Fir............................................................................................... 267

Introduction............................................................................................................... 267

Compatibility............................................................................................................. 267

Timing....................................................................................................................... 267

Grafting Methods...................................................................................................... 267

Rootstocks................................................................................................................. 267

Scion Wood...............................................................................................................268

Systems......................................................................................................................268

Physiological and Environmental Factors................................................................. 270

After Care.................................................................................................................. 270

Growing On............................................................................................................... 271

Chapter 21 Acer (Sapindaceae) – Maple...................................................................................... 273

Introduction............................................................................................................... 273

Compatibility............................................................................................................. 273

Timing.......................................................................................................................280

Grafting Methods...................................................................................................... 281

Rootstocks.................................................................................................................282

Potted, Plug Grown and Bare-Root Rootstocks...................................................283

Scion Wood...............................................................................................................284

Systems......................................................................................................................284

Dormant Season Grafting....................................................................................284

Hot-Pipe System...................................................................................................286

Summer Grafting..................................................................................................286

Physiological and Environmental Factors.................................................................287

Top-Worked Plants....................................................................................................288

After Care..................................................................................................................288

Performance Comparisons........................................................................................289

Growing On...............................................................................................................289

Chapter 22 Actinidia (Actinidiaceae) – Kiwi Fruit...................................................................... 291

Introduction............................................................................................................... 291

Compatibility............................................................................................................. 291

Timing....................................................................................................................... 291

Grafting Methods...................................................................................................... 291

Rootstocks................................................................................................................. 291

Scion Wood...............................................................................................................292

Systems......................................................................................................................292

Physiological and Environmental Factors.................................................................292

Growing On...............................................................................................................292

Chapter 23 Aesculus (Sapindaceae) – Horse Chestnut & Buckeye.............................................293

Introduction...............................................................................................................293

Compatibility.............................................................................................................293

Timing.......................................................................................................................293

Grafting Methods......................................................................................................294

Rootstocks.................................................................................................................294

Scion Wood...............................................................................................................294

Systems...................................................................................................................... 295

Physiological and Environmental Factors................................................................. 295

Top-Worked Trees..................................................................................................... 295

Growing On............................................................................................................... 295

Chapter 24 Amelanchier (Rosaceae) – Snowy Mespilus.............................................................297

Introduction...............................................................................................................297

Compatibility.............................................................................................................297

Timing.......................................................................................................................297

Grafting Methods......................................................................................................297

Rootstocks.................................................................................................................297

Scion Wood...............................................................................................................297

Systems...................................................................................................................... 298

Physiological and Environmental Factors.................................................................298

Growing On...............................................................................................................298

Chapter 25 Aralia (Araliaceae)....................................................................................................299

Introduction...............................................................................................................299

Compatibility.............................................................................................................299

Timing.......................................................................................................................299

Grafting Methods......................................................................................................299

Rootstocks.................................................................................................................302

Scion Wood...............................................................................................................302

Systems......................................................................................................................303

Physiological and Environmental Factors.................................................................303

Growing On...............................................................................................................303

Chapter 26 Berberis & Mahonia (Berberidaceae).......................................................................305

Introduction...............................................................................................................305

Compatibility.............................................................................................................305

Timing.......................................................................................................................305

Grafting Methods......................................................................................................305

Rootstocks.................................................................................................................306

Scion Wood...............................................................................................................306

Systems......................................................................................................................306

Physiological and Environmental Factors.................................................................306

Growing On...............................................................................................................306

Chapter 27 Betula (Betulaceae) – Birch......................................................................................307

Introduction...............................................................................................................307

Compatibility.............................................................................................................307

Timing.......................................................................................................................308

Grafting Methods......................................................................................................308

Rootstocks.................................................................................................................309

Plug Grown Rootstocks........................................................................................ 310

Bare-Root Rootstocks........................................................................................... 311

Scion Wood............................................................................................................... 311

Mother Trees/Storage........................................................................................... 311

Size/Quality.......................................................................................................... 311

Alternative Scion Wood/Scions for Multi-Stemmed Trees.................................. 312

Systems...................................................................................................................... 312

Cold Callusing...................................................................................................... 313

Warm Callusing.................................................................................................... 313

Hot-Pipe................................................................................................................ 313

Late Spring/Early Summer – Late Summer Grafting.......................................... 313

Physiological and Environmental Factors................................................................. 313

Root Pressure/Drying Off.................................................................................... 313

Temperature.......................................................................................................... 314

Graft Infection Treatments................................................................................... 314

Care of Grafts before, during and after Union Formation........................................ 315

Top-Worked and Multi-Stemmed Trees.................................................................... 315

Performance Comparisons........................................................................................ 316

Growing On............................................................................................................... 316

Chapter 28 Camellia (Theaceae).................................................................................................. 317

Introduction............................................................................................................... 317

Compatibility............................................................................................................. 317

Timing....................................................................................................................... 317

Grafting Methods...................................................................................................... 318

Rootstocks................................................................................................................. 319

Scion Wood............................................................................................................... 321

Systems...................................................................................................................... 321

Contents xix

Warm Callusing.................................................................................................... 321

Cuttings-Grafts..................................................................................................... 321

Nurse Seed Grafting............................................................................................. 322

Physiological and Environmental Factors................................................................. 322

Top-Worked Patio Plants........................................................................................... 323

Performance Comparisons........................................................................................ 323

Growing on................................................................................................................ 323

Chapter 29 Carpinus (Betulaceae) – Hornbeam.......................................................................... 325

Introduction............................................................................................................... 325

Compatibility............................................................................................................. 325

Timing....................................................................................................................... 326

Grafting Methods...................................................................................................... 326

Rootstocks................................................................................................................. 327

Scion Wood............................................................................................................... 327

Systems...................................................................................................................... 327

Physiological and Environmental Factors................................................................. 328

Performance Comparisons........................................................................................ 329

Growing On............................................................................................................... 329

Chapter 30 Cedrus (Pinaceae) – Cedar........................................................................................ 331

Introduction............................................................................................................... 331

Compatibility............................................................................................................. 331

Timing....................................................................................................................... 331

Grafting Methods...................................................................................................... 331

Rootstocks................................................................................................................. 331

Scion Wood............................................................................................................... 332

Systems...................................................................................................................... 332

Physiological and Environmental Factors................................................................. 332

Top-Worked Patio Plants........................................................................................... 332

Growing on................................................................................................................ 333

Chapter 31 Cercis (Caesalpiniaceae) – Redbud, Judas Tree........................................................ 335

Introduction............................................................................................................... 335

Compatibility............................................................................................................. 335

Timing....................................................................................................................... 335

Grafting Methods...................................................................................................... 336

Rootstocks................................................................................................................. 337

Scion Wood............................................................................................................... 337

Systems...................................................................................................................... 337

Physiological and Environmental Factors................................................................. 338

Growing on................................................................................................................ 338

Chapter 32 Chamaecyparis Including Xanthocyparis (Callitropsis) (Cupressaceae).................. 341

Introduction............................................................................................................... 341

Compatibility............................................................................................................. 341

Timing....................................................................................................................... 342

Grafting Methods...................................................................................................... 342

Rootstocks................................................................................................................. 342

Scion Wood...............................................................................................................344

Systems......................................................................................................................344

Physiological and Environmental Factors.................................................................344

Top-Worked Patio Plants...........................................................................................344

Growing on................................................................................................................344

Chapter 33 Cornus (Cornaceae) – Dogwoods, Cornels............................................................... 345

Introduction............................................................................................................... 345

Compatibility............................................................................................................. 345

Timing.......................................................................................................................346

Grafting Methods......................................................................................................346

Rootstocks................................................................................................................. 347

Scion Wood............................................................................................................... 347

Systems...................................................................................................................... 350

Physiological and Environmental Factors................................................................. 350

Performance Comparisons........................................................................................ 350

Growing on................................................................................................................ 350

Chapter 34 Corylus (Betulaceae) – Hazel.................................................................................... 351

Introduction............................................................................................................... 351

Compatibility............................................................................................................. 351

Timing....................................................................................................................... 352

Grafting Methods...................................................................................................... 352

Rootstocks................................................................................................................. 352

Scion Wood............................................................................................................... 352

Systems...................................................................................................................... 352

Physiological and Environmental Factors................................................................. 353

Growing on................................................................................................................ 353

Chapter 35 Cupressus (Cupressaceae) – Cypress........................................................................ 355

Introduction............................................................................................................... 355

Compatibility............................................................................................................. 355

Timing....................................................................................................................... 355

Grafting Methods...................................................................................................... 355

Rootstocks................................................................................................................. 355

Scion wood................................................................................................................ 356

Systems...................................................................................................................... 356

Physiological and Environmental Factors................................................................. 356

Growing on................................................................................................................ 356

Chapter 36 Daphne (Thymelaeaceae).......................................................................................... 357

Introduction............................................................................................................... 357

Compatibility ............................................................................................................ 357

Timing....................................................................................................................... 357

Contents xxi

Grafting Methods...................................................................................................... 357

Rootstocks................................................................................................................. 358

Scion Wood...............................................................................................................360

Systems......................................................................................................................360

Physiological and Environmental Factors................................................................. 361

Growing on................................................................................................................ 361

Chapter 37 Fagus (Fagaceae) – Beech......................................................................................... 363

Introduction............................................................................................................... 363

Compatibility............................................................................................................. 363

Timing....................................................................................................................... 363

Grafting Methods......................................................................................................364

Rootstocks ................................................................................................................364

Scion Wood...............................................................................................................364

Systems......................................................................................................................365

Physiological and Environmental Factors.................................................................365

Top-Worked Trees.....................................................................................................365

Growing on ...............................................................................................................366

Chapter 38 Hamamelis (Hamamelidaceae) – Witch Hazel......................................................... 367

Introduction............................................................................................................... 367

Compatibility............................................................................................................. 367

Timing.......................................................................................................................368

Grafting Methods......................................................................................................368

Rootstocks.................................................................................................................368

Scion Wood...............................................................................................................369

Systems...................................................................................................................... 370

Physiological and Environmental Factors................................................................. 371

Growing on................................................................................................................ 371

Chapter 39 Juglans (Juglandaceae) – Walnuts............................................................................. 373

Introduction............................................................................................................... 373

Compatibility............................................................................................................. 373

Timing....................................................................................................................... 374

Grafting Methods...................................................................................................... 374

Rootstocks................................................................................................................. 375

Rootstock Propagation.......................................................................................... 376

Blackline Disease................................................................................................. 378

Scion Wood............................................................................................................... 378

Systems...................................................................................................................... 379

Warm Callusing.................................................................................................... 379

Warm Callusing – Enclosed Conditions.......................................................... 379

Warm Callusing – Callusing Boxes................................................................. 379

Root Grafting........................................................................................................380

Hot-Pipe................................................................................................................ 381

Physiological and Environmental Factors................................................................. 381

Growing on................................................................................................................ 383

Chapter 40 Juniperus (Cupressaceae) – Juniper.......................................................................... 385

Introduction............................................................................................................... 385

Compatibility............................................................................................................. 385

Timing.......................................................................................................................386

Grafting Methods......................................................................................................386

Rootstocks................................................................................................................. 387

Scion Wood...............................................................................................................388

Systems...................................................................................................................... 388

Physiological and Environmental Factors................................................................. 389

Performance Comparisons........................................................................................390

Growing on................................................................................................................390

Chapter 41 Magnolia (Magnoliaceae).......................................................................................... 391

Introduction............................................................................................................... 391

Compatibility............................................................................................................. 391

Timing....................................................................................................................... 393

Grafting Methods...................................................................................................... 394

Rootstocks................................................................................................................. 395

Choice of Alternatives.......................................................................................... 395

Seed-Raised Rootstocks....................................................................................... 396

Cuttings Raised Rootstocks.................................................................................. 398

Conclusions on Rootstocks...................................................................................399

Scion Wood............................................................................................................... 401

Systems......................................................................................................................403

Physiological and Environmental Factors.................................................................404

Growing on................................................................................................................404

Performance Comparisons........................................................................................405

Chapter 42 Malus (Rosaceae) – Flowering Crabs and Orchard Apples......................................407

Introduction...............................................................................................................407

Compatibility.............................................................................................................407

Flowering Crabs...................................................................................................407

Timing.......................................................................................................................408

Grafting Methods......................................................................................................408

Rootstocks.................................................................................................................409

Ornamental Crabs................................................................................................409

Orchard Apples.....................................................................................................409

Double-Working.............................................................................................. 410

Scion Wood............................................................................................................... 410

Systems...................................................................................................................... 413

Physiological and Environmental Factors................................................................. 413

Top-Worked Trees..................................................................................................... 413

Growing on................................................................................................................ 413

Chapter 43 Paeonia (Paeoniaceae) – Tree Paeony....................................................................... 415

Introduction............................................................................................................... 415

Compatibility............................................................................................................. 415

Timing....................................................................................................................... 415

Grafting Methods...................................................................................................... 415

Rootstocks................................................................................................................. 416

Scion Wood............................................................................................................... 417

Systems...................................................................................................................... 417

Physiological and Environmental Factors................................................................. 419

Growing on................................................................................................................ 419

Chapter 44 Picea (Pinaceae) – Spruce......................................................................................... 421

Introduction............................................................................................................... 421

Compatibility............................................................................................................. 421

Timing....................................................................................................................... 421

Grafting Methods...................................................................................................... 422

Rootstocks................................................................................................................. 423

Scion Wood...............................................................................................................424

Systems...................................................................................................................... 425

Physiological and Environmental Factors................................................................. 426

Top-Worked Plants.................................................................................................... 428

Growing on................................................................................................................ 429

Chapter 45 Pinus (Pinaceae) – Pines........................................................................................... 431

Introduction............................................................................................................... 431

Compatibility............................................................................................................. 431

Timing....................................................................................................................... 433

Grafting Methods...................................................................................................... 433

Rootstocks................................................................................................................. 434

Scion Wood............................................................................................................... 434

Systems...................................................................................................................... 435

Physiological and Environmental Factors................................................................. 437

Performance Comparisons........................................................................................ 437

Top-Worked Plants.................................................................................................... 438

Growing on................................................................................................................ 438

Chapter 46 Prunus (Rosaceae) – Ornamental Prunus................................................................. 439

Introduction............................................................................................................... 439

Compatibility............................................................................................................. 439

Timing.......................................................................................................................442

Grafting Methods......................................................................................................442

Rootstocks.................................................................................................................442

Scion Wood...............................................................................................................443

Systems......................................................................................................................443

Physiological and Environmental Factors.................................................................444

Top-Worked Plants....................................................................................................444

Growing on................................................................................................................444

Chapter 47 Prunus (Rosaceae) – Almonds and Stone Fruits.......................................................445

Introduction...............................................................................................................445

Compatibility.............................................................................................................445

Timing.......................................................................................................................445

Grafting Methods......................................................................................................445

Rootstocks.................................................................................................................445

Almonds...............................................................................................................446

Apricots................................................................................................................446

Peaches and Nectarines........................................................................................446

Plums.................................................................................................................... 450

Apriums and Pluots.............................................................................................. 450

Sweet and Sour Cherries...................................................................................... 450

Scion Wood............................................................................................................... 452

Systems...................................................................................................................... 452

Physiological and Environmental Factors................................................................. 452

Chapter 48 Pyrus (Rosaceae) – Ornamental and Fruiting Pears................................................. 453

Introduction............................................................................................................... 453

Compatibility............................................................................................................. 453

Ornamental Pears................................................................................................. 453

Fruiting Pears....................................................................................................... 454

Timing....................................................................................................................... 455

Grafting Methods...................................................................................................... 456

Rootstocks for Fruiting Pears.................................................................................... 456

Scion Wood............................................................................................................... 457

Systems...................................................................................................................... 457

Physiological and Environmental Factors................................................................. 457

Top-Worked Plants.................................................................................................... 457

Growing on................................................................................................................ 457

Chapter 49 Quercus (Fagaceae) – Oaks....................................................................................... 459

Introduction............................................................................................................... 459

Compatibility............................................................................................................. 459

Further Discussion on Compatibility...................................................................460

Subgenus Cyclobalanopsis...............................................................................460

Subgenus Quercus: Section Cerris...................................................................462

Subgenus Quercus: Sections Mesobalanus and Quercus.................................462

Subgenus Quercus: Section Protobalanus........................................................463

Subgenus Quercus: Section Lobatae................................................................463

Inter-Sectional Combinations – Potential Inter-Stems....................................463

Effects of Particular Combinations.................................................................464

Timing.......................................................................................................................464

Grafting Methods......................................................................................................464

Rootstocks.................................................................................................................466

Pot and Plug Grown Rootstocks...........................................................................466

Bare-Root Rootstocks...........................................................................................467

Root Grafts...........................................................................................................467

Scion Wood...............................................................................................................467

Systems......................................................................................................................468

Warm Callusing....................................................................................................468

Hot-Pipe................................................................................................................469

Root Grafting........................................................................................................469

Nurse-Seed Grafting............................................................................................469

Physiological and Environmental Factors................................................................. 470

Performance Comparisons........................................................................................ 470

Growing on................................................................................................................ 470

Chapter 50 Rhododendron (Ericaceae)........................................................................................ 471

Introduction............................................................................................................... 471

Compatibility............................................................................................................. 471

Timing....................................................................................................................... 473

Grafting Methods...................................................................................................... 473

Rootstocks................................................................................................................. 475

Rootstock Selection.............................................................................................. 475

Rootstocks for Large Leaved Types..................................................................... 476

Rootstock Stem..................................................................................................... 477

Pot Grown versus Bare-root................................................................................. 478

Raising Clonal Rootstocks................................................................................... 478

Specifications........................................................................................................ 479

Scion Wood............................................................................................................... 479

Systems...................................................................................................................... 481

Management of Rootstock – Heading-back.........................................................482

Summer Grafting..................................................................................................482

Cuttings-Grafts.....................................................................................................483

Modified Cuttings-Grafts.....................................................................................485

Physiological and Environmental Factors.................................................................486

Top-Worked Plants....................................................................................................488

Growing on................................................................................................................488

Chapter 51 Sorbus (Rosaceae) – Mountain Ash, Whitebeam.....................................................489

Introduction...............................................................................................................489

Compatibility.............................................................................................................489

Timing....................................................................................................................... 491

Grafting Methods......................................................................................................492

Rootstocks.................................................................................................................492

Scion Wood...............................................................................................................492

Systems......................................................................................................................492

Physiological and Environmental Factors.................................................................492

Growing On...............................................................................................................492

Chapter 52 Syringa (Oleaceae) – Lilac, French Lilac.................................................................. 493

Introduction............................................................................................................... 493

Compatibility............................................................................................................. 493

Timing.......................................................................................................................494

Grafting Methods......................................................................................................494

Rootstocks................................................................................................................. 495

Scion Wood...............................................................................................................496

Systems......................................................................................................................496

Field Planting........................................................................................................497

Potting Up/On.......................................................................................................497

Summer Grafting..................................................................................................497

Cuttings-Grafts.....................................................................................................497

Physiological and Environmental Factors................................................................. 498

Top-Worked Plants.................................................................................................... 498

Growing On............................................................................................................... 498

Chapter 53 Tilia (Malvaceae) – Lime-trees, Lindens, Basswoods..............................................499

Introduction...............................................................................................................499

Compatibility.............................................................................................................499

Timing.......................................................................................................................500

Grafting Methods......................................................................................................500

Rootstocks.................................................................................................................502

Scion Wood...............................................................................................................503

Systems......................................................................................................................503

Physiological and Environmental Factors.................................................................504

Growing On...............................................................................................................504

Chapter 54 Viburnum (Adoxaceae).............................................................................................505

Introduction...............................................................................................................505

Compatibility.............................................................................................................505

Timing.......................................................................................................................506

Grafting Methods......................................................................................................507

Rootstocks.................................................................................................................507

Scion Wood...............................................................................................................508

Systems......................................................................................................................508

Physiological and Environmental Factors.................................................................508

Top-Worked Plants....................................................................................................508

Growing On...............................................................................................................509

Chapter 55 Vitis (Vitaceae) – Vines, Grapevines........................................................................ 511

Introduction............................................................................................................... 511

Compatibility............................................................................................................. 511

Timing....................................................................................................................... 511

Grafting Methods...................................................................................................... 511

Rootstocks................................................................................................................. 512

Scion Wood............................................................................................................... 513

Systems...................................................................................................................... 513

Physiological and Environmental Factors................................................................. 515

Growing On............................................................................................................... 516

PART EIGHT Genera Grafting Guide Tables

Chapter 56 Grafting Table List.................................................................................................... 519

Introduction............................................................................................................... 519

APPENDICES

Appendix A: List of Families and Genera Field Grafted.......................................................... 557

Appendix B: List of Families Bench Grafted and with Potential to Graft.............................. 559

Appendix C: Practice Holders..................................................................................................... 561

Appendix D: Outputs for Bench Grafting.................................................................................. 563

Appendix E: Knife Types Other than Tina................................................................................565

Appendix F: Knife Sharpening – Cutting Edge Grind Types.................................................. 567

Appendix G: Types of Sharpening Stones.................................................................................. 569

Appendix H: Honing - Strops and Honing Machines - Corrosion Prevention....................... 571

Appendix I: Sharpening Aids...................................................................................................... 573

Appendix J: Knife Sharpening Machines.................................................................................. 575

Appendix K: Grafting Machines and Grafting Tools............................................................... 577

Appendix L: Workstations: Integral, Static and Mobile.......................................................... 581

Appendix M: Grafting Bench Design and Construction.......................................................... 583

Appendix N: Seat Design.............................................................................................................. 585

Appendix O: Lighting Levels for Grafting Benches.................................................................. 587

Appendix P: Effect of Fungicides on Graft Success.................................................................. 589

Appendix Q: Design and Construction of Free-Standing, Walk-In Grafting Polytunnels......... 591

Appendix R: Hot-Pipe Solid Cover Heating Chamber Dimensions......................................... 593

Appendix S: ‘Economy’ Hot-Pipe Design................................................................................... 595

Bibliography.................................................................................................................................. 597

Plant Index..................................................................................................................................... 611

Index............................................................................................................................................... 629

Brian Humphrey commenced work in local nurseries in 1954 followed by two years National Service in the Royal Air Force before taking up a studentship at the Royal Botanic Gardens, Kew. A two-year studentship at Writtle Agricultural College (now Writtle University College) followed, and provided the opportunity to gain the Royal Horticultural Society’s National Diploma (now Master of Horticulture) with Honours.

Joining Hillier Nurseries in 1963 as a propagator, he became a member of the Plant Propagator’s Society based in the US in 1964 and aided in the formation of the first overseas chapter of the Society, the GB and I Region, in 1968–69. He was the inaugural President of the region in 1969 and was awarded the International Award of Honour by that Society in 1993.

Promotion at Hilliers lead to the position of Production Director and the opportunity to develop various aspects of the nursery, which, at that time, grew commercially the widest range of temperate woody plants in the world. Joining Notcutt’s Nurseries in 1986 provided opportunities for further experience. Prior to retirement, over a decade was spent running his own wholesale nursery specialising in grafted plants.

Involvement and subsequent chairmanship of the UK ornamental nursery industry research and development initiatives with the UK Ministry of Agriculture led to the award of an O.B.E. (Order of the British Empire) in 1987. In 2013, his work in the nurserystock industry and in various

RHS projects was recognised by the award of the VMH (Victoria Medal of Honour) by the Royal Horticultural Society.

He now lives in retirement in coastal Suffolk, eastern England and together with his wife maintains their garden with nearly seven acres of woodland and meadows of woody plants.