This publication comprises the proceedings of the first International Conference devoted to the structural roots of trees and woody plants. 'The Supporting Roots - Structure and Function,' 20-24 July 1998, Bordeaux, France. The meeting was held under the auspices ofIUFRO WPS 2. 01. 13 'Root Physiology and Symbiosis,' and its aim was to bring together scientific researchers, foresters and arboriculturalists, to discuss current problems in structural root research and disseminate knowledge to an audience from a wide disciplinary background. For the first time in an international conference, emphasis was placed on presenting recent reseach in the field of tree anchorage mechanics and root biomechanics. The way in which tree stability can be affected by root system symmetry and architecture was addressed, as well as how movement during wind sway can influence the development and shape of woody roots. The role of different nursery and planting techniques was discussed, in relation to effects on root system form and development. Root response to different environmental stresses, including water, temperature, nutrient and mechanical stress was addressed in detail. The structure and function of woody roots was also considered at different levels, from coarse to fine roots, with several papers discussing the interaction between roots and the rhizosphere. One of the conference highlights was the presentation of new methods in root research, by a series of workshops held at LRBB-INRA, Pierroton, on the northern border of the Gascony forest.

Inhalt
Anchorage and Biomechanics.- 1. The development of symmetry, rigidity and anchorage in the structural root system of conifers.- 2. Strain distribution during anchorage failure of Pinus pinaster Ait. at different ages and tree growth response to wind-induced root movement.- 3. Root deformation in plantations of container-grown Scots pine trees: effects on root growth, tree stability and stem straightness.- 4. Root strength, growth, and rates of decay: root reinforcement changes of two tree species and their contribution to slope stability.- 5. A study on the adaptability mechanism of tree roots on steep slopes.- Structural Root System Architecture in Forest Trees.- 6. Structural root architecture of 5-year-old Pinus pinaster measured by 3D digitising and analysed with AMAPmod.- 7. Genetics of root architecture in 1-year-old Pinus pinaster measured with the WinRHIZO image analysis system: preliminary results.- 8. Root architecture, early development and basal sweep in containerized and bare-rooted Douglas fir (Pseudotsuga menziesü).- 9. The effect of cultivation technique on root and shoot biomass production by young Sitka spruce (Picea sitchensis (Bong.) Carr.) trees on surface water gley soils.- 10. Influence of cultivation method on root grafting in Norway spruce (Picea abies (L.) Karst.).- Growth and Development.- 11. Comparison of radial increment and volume growth in stems and roots of Quercus petraea.- 12. Tree root system enhancement with paclobutrazol.- 13. Clonal strategies of a woody weed: Melia azedarach.- 14. Clonal variation in above- and below-ground growth responses of Populus tremuloides Michaux: influence of soil warming and nutrient availability.- 15. Above- and below-ground growth of white spruce seedlings with roots divided into different substrateswith or without controlled-release fertilizer.- 16. Heritability of first-order lateral root number in Quercus: implication for artificial regeneration of stands.- 17. Root-infecting fungi associated with a decline of longleaf pine in the southeastern United States.- Modelling of Growth, Development and Architecture.- 18. Why model root system architecture?.- 19. A model simulating interactions between plant shoot and root architecture in a non-homogeneous environment.- 20. Why are laterals less affected than main axes by homogeneous unfavourable physical conditions? A model-based hypothesis.- Responses to Abiotic Stress.- 21. The effects of wind speed and direction on radial growth of structural roots.- 22. Responses of sap flow rate along tree stem and coarse root radii to changes of water supply.- 23. Water conductance and osmotic potential of papaya (Carica papaya L.) roots as influenced by drought.- 24. Effect of water stress on root meristems in woody and herbaceous plants during the first stage of development.- 25. Influence of soil temperature on root freezing tolerance of Scots pine (Pinus sylvestris L.) seedlings.- 26. Sucrose metabolism, growth and transplanting stress in sweetgum seedling taproots and stems.- New Methods in Root Research.- 27. A method for predicting the possible site of failure in trees during mechanical loading. Method for predicting tree failure.- 28. Review of in situ shear tests on root reinforced soil.- 29. An experimental study on the mechanical behaviour of the maize root system: analysis of the soil/root bond and determination of rigidity modulus.- 30. Distribution of Armillaria on pear root systems and a comparison of root excavation techniques.- 31. An approach to minirhizotron root image analysis.- 32. A field method of determining NH4+ and NO3? uptake kinetics in intact roots: effects of CO2 enrichment on trees and crop species.- Fine and Woody Root Characteristics, Ultrastructure and Rhizosphere.- 33. Adaptive tactics and characteristics of tree fine roots.- 34. Pine root structure and its potential significance for root function.- 35. Tracheids in white spruce seedling's long lateral roots in response to nitrogen availability.- 36. The efficiency of the water conducting system of tomato roots. Hydraulic conductivity of tomato roots.- 37. Root structure and arbuscular mycorrhizal colonization of the palm Serenoa repens under field conditions.- 38. Is maintenance respiration in roots a constant?.- 39. Is the root system the key to higher nitrogen uptake in rapeseed? The case of a composite hybrid line.- 40. Effects of liming on rhizosphere chemistry and growth of fine roots and of shoots of sessile oak (Quercus petraea).- 41. A new approach to the investigation on the tonogenic groups of root cell walls.