BLACK CUTToN SOILS 



GOSSYPIUM 



^^H SOILS AND 



MANURE 



states that in tin- xiinpli-s la- examined, the amount of phosphoric a 



li Muall, was more than in other Indian soils. The commonest form 



t soil is a sandy clay coloured by iron peroxide. It may be derived 

 I mi 1 1 tin- rocks in situ or from the same products of decomposition washed 

 I iy r.iin to lower levels. Laterite soils are simply soils lying on or adjacent 

 rite rocks. The composition of both these classes, according to 



icr's analyses, varies considerably, but, like other soils of India, both 

 are deficient in phosphoric acid and nitrogen. 



It is on the black cotton or regur soils that Indian cottons are generally Regur 



ii. Typical regur areas are well represented in the Bombay and Soils. 

 Madras Presidencies. The condition indicated may be described as a 

 highly argillaceous, calcareous clay, very adhesive when wet, and from 

 its absorbent nature expanding and again contracting to a remarkable 

 xtcnt. In consequence, during the hot weather, such soils become 

 fissured in every direction by huge cracks, which in depth vary greatly. 

 In some parts, for example at Akola, they have been reported as seen from 

 40 to 60 feet deep. Underlying the regur is a bed of yellow-white earth 

 consisting of clay, lime and sand intimately mixed. It has generally been 

 supposed that the black colour is due to an admixture of organic matter, 

 but Leather is of opinion that this cannot be the case, but that it must be 

 due to the presence of some mineral substance. He also holds that these 

 soils are not inordinately fertile. In the matter of phosphoric acid and 

 nitrogen they are very poor. The fact that they do produce crops liberally, 

 he thinks, is due to their power of retaining moisture and to their contrac- 

 tion, which not only forms deep and wide fissures, but causes the surface 

 to crumble to a powder, which, getting carried into the larger fissures, 

 thus brings about a continual inversion of the soil. 



As regards the manuring of cotton crops, it has been proved by ex- Manure, 

 periment that cotton responds promptly and profitably to a judicious 

 fertilisation. The following account is taken from the results of the 

 experiments carried out by the United States Department of Agriculture. 

 It may be stated in the first place that a complete fertiliser is needed for complete 

 cotton, i.e. one containing soluble phosphoric acid, potash and nitrogen. Fertuiser - 

 Neither phosphoric acid nor potash give as good results separately as 

 when combined. The most effective constituent is phosphoric acid, 

 but nitrogen alone has little or no effect. The best form of nitrogenous 

 manure appears to be cotton-seed meal and nitrate of soda. The pro- cotton-seed 

 portions of the three constituents in a complete fertiliser should accord- meaL 



B ly be approximately, nitrogen 1 part ; potash 1 part ; phosphoric acid 

 3 parts. The quantity used per acre varies widely with the nature and 

 condition of the soil, but the maximum should be an amount yielding 

 nitrogen 20 Ib ; potash 20 Ib. ; phosphoric acid 70 Ib. The profit from 

 manuring cotton is much increased by antecedent proper preparation 

 of the soil. Farmyard and similar bulky manures are said to be more 

 efficient as soil-renovators than as specific fertilisers for cotton. The soii-renovatore. 

 concentrated fertiliser should be applied in the drill, not broadcasted, at 

 a depth of not more than 3 inches, and well mixed with the soil. 



[Cf. Voelcker, Itnproo. 2nd. Agri., 1893, 47, etc. ; McBryde, Fert. for Cotton, 



U.S. Dept. Agri. Bull. 1894, No. 14; Anderson, Fert. required by Cotton, etc., Agri. 



!>. Stat., Auburn, Alabama, Bull. May 1894, No. 57; White, The Manuring of 



Cotton, in Dabney, The Cotton Plant, etc., 1896, 169-96; Duggar, Co-oper. Fert. 



th Cotton, Agri. Exper. Stat., Auburn, Alabama, Bull. Feb. 1899, No. 102 : 



:!is.,n, Textbook, Ind. Agri., 1901, i., 22-3, 28-31; Francis Watts, Manur- 



609 



39 



