5IO SECTIONAL TRANSACTIONS.— K*. 



in home-grown hardwoods are largely due to silvicultural mistakes or 

 neglect. Reference is made to particular defects in oak, beech, ash, birch, 

 etc. Attention is drawn to the importance of plywood as an outlet for 

 home grown timber and the need for careful silviculture. Charcoal as a 

 means of disposing of cordwood is touched on. 



Discussion (10.20). 



Afternoon. 

 Excursion to Cambridge Experimental Area and Conington Hall. 



Saturday, August 20. 



Excursion to Mr. W. J. Burton's Chip Basket Factory at Wisbech ; 

 Ryston Estate ; and Forestry Commission's Nursery, Mundford. 



Sunday, August 21. 



Excursion to Forestry Commissions Plantations in Thetford Forest. 



Monday, August 22. 



Joint Discussion with Section K (Botany) on The ecological aspects of 

 afforestation (lo.o). 



Dr. A, S. Watt. — The significance of Breckland in British forestry. 



The climate, soil and vegetation are considered in formulation of general 

 principles governing the practice of forestry in Breckland. 



Dr. H. M. Steven. — The ecological aspects of afforestation in hill 

 country (10.45). 



Mr. R. Ross. — The colonisation of abandoned agricultural land in 

 south-west Cambridgeshire (11. 15). 



The Chalky Boulder Clay of south-west Cambridgeshire gives rise to 

 very heavy clay soils, the natural vegetation of which is ash-oak woodland. 

 On this formation considerable areas of agricultural land have gone out of 

 cultivation during the last hundred years. These have become covered 

 by a scrub dominated by Cratcegus in the early stages of which a few 

 seedlings of Qiiercus and Fraxinus develop under the bushes and survive. 

 Animal, probably rabbit, attack severely limits the numbers. Ulmus 

 minor becomes established freely by suckers at this time close to hedges 

 containing the species. At a later stage, when the scrub becomes denser, 

 further establishment of trees becomes impossible and almost all the 

 ground vegetation is killed. The Cratcegus is not regenerating, apparently 

 owing to caterpillar attack of the seedlings, and will therefore die out in 

 time. By then the soil will have been considerably altered, having acquired 

 much humus and an open crumb structure. It appears likely that trees, 

 particularly Ulmus minor, will then be able to establish themselves, and it 



