VARIATIONS IN PASTURES 137 



than o"oi per cent, potash soluble in 1 per cent, citric acid (avail- 

 able), the authors consider an application of potash salts is 

 likely to be useful. With regard to lime, unless a pasture soil 

 contain less than 0*25 per cent, it seems improbable that liming 

 is necessary. 



The mechanical composition of the soil is probably the 

 factor of prime importance to take into account in attempting 

 to improve poor pasturage. A fairly good mechanical condition 

 is essential: soils with a very high proportion of either the 

 coarsest or the finest grades of particles are never likely to make 

 really useful grazing land, whatever the manurial treatment. 



A further paper by S. F. Armstrong 1 (also from the Cambridge 

 School of Agriculture) deals primarily with the botanical and 

 chemical composition of the herbage of pastures and meadows 

 but includes observations on the soils of the grass lands 

 investigated. It was apparent that, at all events in the English 

 Midlands, the choicest grazing land was invariably associated 

 with soil rich in " available " phosphates ; here again the import- 

 ance of good physical condition and of an abundant supply of 

 11 available " phosphoric acid for the production of good pasture 

 land is emphasised. 



To what extent these conclusions hold good for pasture soils 

 generally can only be determined when we are in possession of 

 many more data on the subject. 



Romney Marsh Soils. — An important local problem has 

 received attention in the very thorough investigation recently 

 carried out by Hall and Russell 2 of the Rothamsted Experi- 

 mental Station on the pasture soils of Romney Marsh. 

 Romney Marsh, which has an area of nearly 120 square miles, 

 is part of the large stretch of alluvial land which borders 

 much of the coasts of Kent and Sussex. It is only slightly 

 elevated above high-water mark but having been elaborately 

 drained is now dry and can no longer properly be called a 

 marsh. It is almost entirely grass land. In spring and summer 

 the fields are occupied by great numbers of sheep, as they 

 form some of the best grazing land in the south of England, 

 many of the pastures being famous for their richness. The best 

 land will fatten as many as ten sheep per acre during the sum- 

 mer without the aid of any artificial feeding ; but all the pastures 



1 Jour. Agric. Science, vol. ii. p. 283. 



2 Ibid. 1912, vol. iv. No, 4. 



