SECTIONAL TRANSACTIONS. — K. 373 



Thursday, August 26. 



Joint Discussion with Section M on Soil and Plant Survey Work. 



Botanical part of the duscussion centred round : 



(i.) Types of grassland in view of importance in Wales 

 and in general in agriculture — the possibility of recognising 

 a number of types in different parts of the country. 



(ii.) Possibility of fixing on some standard symbols or 

 colours for ecological mapping. 



(iii.) Relation of ecological data to geological data. 



(iv.) Study and representation of arable. 



12. Mr. G. W. EoBiNSON. — Soil Types of North Wales. 



It is suggested that while uniformity in sampling and 

 analytical methods should be secured, the classification of 

 soils must depend on the local conditions. In extreme humid 

 conditions it would appear that differences due to geological 

 factors tend to be obliterated. Large numbers of soil samples 

 should be collected and the fypes should be worked out from 

 actual observations, correlation with geology may follow 

 afterwards. The soil survey gives information as to one of 

 the factors affecting plant growth and, ultimately, agricul- 

 ture in a particular area. The survey in its widest sense 

 should take cognisance of all the other factors, including 

 climate and soil-water conditions. The vegetation survey 

 gives the results of the operation of all these factors. 



1 3. Mr. E. A. Fisher. — Soil Acidity. 



14. Prof. E. G. Staplbdon. — Surveys of Grassland Districts. 



Re (i.) A method of obtaining quantitative data ; sub- 

 division of grassland ; Fescue Agrostis pastures in detail. 

 Effect of grazing animals. 



He (ii.) Colour scheme must allow for transitions; sub- 

 types by ink symbols on a ground colour. 



Ee (iv.) Use of weed flora in representation of arable. 



Importance of primary survey. 



15. Miss W. H. WoRTHAM. — The Vegetation of Anglesey and 



N. Carnarvonshire, with special reference to the Grass- 

 lands. 



Until about 700 years ago the vegetation of Anglesey 

 and N. Carnarvonshire comprised : 



(1) an area of moorland stretching up from the 1000-1700 

 contours over the Carnarvonshire mountains, interrupted only 

 by the associations of the summits, rock-ledges and screes ; 



(2) A zone of woodland extending from the edge of the 

 moorland to sea-level, interrupted by marshes and by lowland 

 moors. The plant formations are closely related to the 

 geological structure of the district. The greater part of the 

 uncultivated area is now grassland and may be summarised 

 thus : (i) the sub-alpine grassland which has been derived 

 from upland moor, (ii) The siliceous, schistose, and cal- 

 careous grasslands which have been derived from the corre- 

 sponding woodlands, (iii) Molinia grassland formed (a) as 

 a product of the degeneration of woodland, or (6) as a 

 primary association developed on wet rocks ; 



(3) Grassland, siliceous, schistose, or calcareous, according 

 to the nature of the soil, has also been formed by the 

 degeneration of lowland moor, the draining of the marshes, 

 the colonisation of screes, and the colonisation of sand-dunes 



