Willowmead,

Ickleton Road,
Wantage,
OX12 9JA.

Tel: 01235 762478
Mob: 07966 503162
biddle@willowmead.co.uk

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14 August 2012

Table of Contents (1)

Chapter 1. Introduction

The case for trees
The case against trees
The nature of the problem
A multi-disciplinary approach
The extent of the problem
Summary

Chapter 2. The Tree
Xylem
Phloem
Cambium and growth
The control of growth, and carbon economy
Leaf function and transpiration
Moisture deficits, suction and water potential
Relationship between growth and transpiration rate
Annual cycle of growth
Summary

Chapter 3. The Root System
Introduction
Overall shape of root system
The root:shoot ratio
Initial root growth
The fine, moisture-absorbing, roots
Factors affecting root growth
Control of root growth
Conducting roots
Structural roots
Root mortality
Root regeneration
The root as a storage organ
Summary

Chapter 4. The Soil
Introduction
The origins of soils
Particle size
Mineralogy of clay
Water and clay minerals
Behaviour of water in sandy soils
Behaviour of clay soils;
a) moisture release
b) shrinkage
Behaviour of soils of intermediate structure
Soil moisture deficit
Soil moisture deficits and soil shrinkage
Soil cracking
Shrinkage and swelling potential
Relevance of plasticity index to soil shrinkage
in the field
Soil permeability
Relationship between gravimetric and volumetric
moisture content
Water potential and moisture content
Summary

Chapter 5. Seasonal Changes in Soil Moisture Content

Introduction
Seasonal development of soil drying
Seasonal development of moisture deficit
Seasonal fluctuations of soil moisture deficit
Soil drying by evergreen vegetation
Soil drying by grass
Soil drying in absence of vegetation
Seasonal fluctuations in water table
Influence of soil type on seasonal moisture deficits
Effect of pruning on seasonal changes
Summary

Chapter 6. Persistent Moisture Deficits
Assumed persistent deficits
Development and maintenance of persistent deficit
Recovery from persistent deficit
Recovery from persistent deficit as result of overmaturity
Factors conducive to development of persistent deficit
Effect of pruning on persistent deficit
Summary

Chapter 7. Interaction Between Trees and Buildings
Introduction
Soil movements
Seasonal movements
Influence of foundation load
Effect of dynamic foundation movement
Movements caused by persistent deficits
The effect of the development of a persistent deficit
on a building
Heave as result of building on a pre-existing persistent
deficit
Angular distortion and damage
Influence of building on soil permeability
Influence of building on root growth
Exclusion of rainfall by buildings and other impermeable
surfaces
Summary

Chapter 8. Influence of the Weather
Introduction
Evolution of MORECS Versions 1.0 and 2.0
Available water content
SMD modelling for different crops
Comparison between years
Comparison of SMD in different areas
Comparison between calculated and actual SMD
Limitations of calculated SMD
Global warming and climate change
Summary

Arboricultural Consultant

P.G. Biddle

Dr P.G. Biddle, O.B.E., M.A., D.Phil., F.Arbor.A.
Registered Consultant of the Arboricultural Association
Honorary Fellow, Insitute of Chartered Foresters

Chapter 9. Comparative Effects of Different Species, and of Individual Trees and Groups

Phenotypic variation
Intra-specific variation
Is inter-specific variation to be expected?
Criteria for comparing effect of different
species on soil and buildings
Rank order based on radial spread of roots
Rank order based on propensity to cause
damage
Rank order based on 'water demand'
Stock / scion interaction
The effects of rows and groups of trees
Shrubs
Summary

Chapter 10. Other Forms of Damage by Tree
Roots
Causes of Damage
Objectives of investigation
Scope of investigations
The role of monitoring
Cost effectiveness of investigation
Reviewing the results of investigations
Summary

Chapter 11. Strategy for Investigating Damage
Causes of Damage
Objectives of investigation
Scope of investigations
The role of monitoring
Cost effectiveness of investigation
Reviewing the results of investigations
Summary

Chapter 12. Site Investigations I) The Building
Objectives
History of site
Analysis of damage to the building
History of damage
Recording of cracks
Severity of damage
Measurement of the distortion of the building
Methods of measuring levels:
i) Water level
ii) Optic level
Levelling staff
Presentation of level results
Interpretation of level surveys
Verticality survey
Foundation depth and construction
Foundation load
Drain and services survey
Summary