426 SECTIONAL TRANSACTIONS.— K*. 



for the bad conditions. Naturally where both rock and weather are un- 

 favourable the worst types of ground occur — here a peat layer almost 

 invariably exists. Roughly these peat-clad sites may be divided into three 

 classes : basins, slopes and knolls. Afforestation experiments have been 

 proceeding on such sites for the last ten to fifteen years, and the interim 

 results or tendencies are already of considerable interest. There have 

 also been many experiments laid down on two other difficult types : (i) 

 Calluna-clad moorlands on which a dry raw-humus takes the place 

 of the peat layer, and (2) dry Calluna-clad, often morainic slopes, where 

 the raw-humus layer is scanty or absent. On the poorer peat sites the 

 difficulty is to get any tree species to become established ; on the dry 

 heather ground the problem is rather the establishment of a more valuable 

 crop than Scots pine, which it is known would grow more or less vigorously. 



Dr. A. B. Stewart. — Some soil problems in forest nurseries (12.20). 



To illustrate the type of information which may be obtained from a soil 

 examination reference may be made to some results which have been 

 obtained for different nursery soils. 



It was found that Scots pine seedlings from soil A showed marked ' brown- 

 ing,' whilst normal healthy plants were obtained in soil B. Specimen plants 

 were taken for analyses from these two soils, and it was found that the 

 healthy plants from soil B had a lime content in their ash of approximately 

 20 per cent. CaO, a figure which agrees well with that given by Manshard 1 

 as typical of normal seedlings. The lime content of the ash of the affected 

 plants from soil A was approximately 40 per cent. CaO. Soil A was found 

 to be much richer in lime and lower in both phosphoric acid and potash 

 than soil B. It appears likely therefore that the poor results obtained in 

 soil A are to be associated to some extent at least with the unfavourable 

 nutrient balance in the soil, where the ratio of calcium to other nutrients, 

 particularly potassium, is very high. That the high calcium content in 

 itself is not likely to have been wholly responsible for the ' browning ' of 

 the seedlings is borne out by the observation that normal healthy plants 

 can be grown in soil C. This has also a very high lime content, but is very 

 much richer in readily soluble phosphoric acid and potash and has a more 

 balanced nutrient content than soil A. 



Experiments are at present being conducted in conjunction with the 

 Forestry Commission (Scotland) in order to obtain more accurate informa- 

 tion on the amounts of lime, phosphoric acid, potash and other nutrients 

 which should be added in order to obtain in the soil the most suitable 

 nutrient balance. 



Friday, September 11. 



Discussion on The utilisation of home-grown timber (10.0). 



Rt. Hon. Lord Clinton. — The position of private estates in the pro- 

 duction of timber. 



Mr. F. G. O. Pearson. — The existing outlets for home-grown timber. 



If afforestation is to pay, the produce of plantations must be utilised at 

 every stage of growth. 



1 Tharandter Forst. J ahrbuch, 84, 2. 1933. 



