90 SCIENTIFIC SURVEY OF YORK AND DISTRICT 



The wide flat which lies between the hills of Surrey and Kent and 

 the Downs of Sussex may vie with it in extent but not in general 

 fertility. If we estimate the Vale of York by the number and 

 copiousness of its rivers and by the richness of its marginal banks, it 

 would perhaps be difficult in any country to equal it.' 



THE SOILS OF THE VALE OF YORK 



BY 



H. T. JONES, M.Sc. 



The whole of the Vale of York is covered by transported material, 

 except for a few outcrops of Jurassic and Triassic rocks, and in some 

 parts the depth of the drift exceeds 150 feet. The relations of the 

 glaciation of this area, to which reference has been made in earlier sections, 

 are therefore of first importance. 



The Teesdale glacier terminated at the Wheldrake moraine, which 

 sweeps in a crescent form from Stamford Bridge to Bolton Percy. On 

 the retreat and subsequent advance of this glacier, another moraine was 

 formed extending from Sand Hutton in the east to Healaugh in the west, 

 and passing through York and the University Farm at Askham Bryan. 

 The first moraine consists of a ridge of boulder-clay of a reddish colour 

 and derived mainly from Triassic material ; the other contains a large 

 proportion of gravel consisting of Shap Granite, Bunter and Carboniferous 

 Limestone. The melt-waters from the glacier were hemmed in on the 

 east by the North Sea glacier covering Holderness and the mouth of the 

 Humber ; consequently a large lake was formed in the southern part of 

 the Vale. The deposits of this lake are of such a depth as to obscure the 

 Wheldrake moraine along portions of its length, especially in the neigh- 

 bourhood of Escrick. The soil so formed shows enormous variation in 

 texture, soil reaction and other characteristics. Within a very small 

 compass, representatives of the lightest and the heaviest soils may be 

 found. This variation is most pronounced in the district south of Escrick 

 and in the neighbourhood of Everingham, and is naturally reflected in 

 the cropping capacity of the soil. 



The sandy soils (post-glacial sands), containing between 3 per cent, and 

 8 per cent, of the clay fraction and about 4 per cent, organic matter, are 

 deficient in lime and require liberal manuring. They depend for their 

 fertility on a fairly high water table, for their water-holding capacity is 

 very low. With adequate manuring, they are suitable for potatoes, 

 this being the most important crop in the Selby area. Sugar-beet, how- 

 ever, is to some extent displacing potatoes, but can be grown successfully 

 only if the soil be limed. 



The heavy soils (lacustrine clay) almost invariably contain a high 

 percentage of calcium carbonate (about 10 per cent.). Owing to diffi- 

 culties of cultivation only a relatively small proportion of the clay is under 

 the plough, and the area under grass is increasing annually. On a few 

 farms this material is used for marling the sandy sour soils, as much as 

 80 tons per acre being applied. 



