242 Ay ricHltuml Gazette of y.S.W. " [April ^A^2Q. 



fertilisers in all cases. On land that is less fertile than the avei'age, or that 

 is lacking in organic matter, these nitrogenous fertilisers c^uld, perhaps, be 

 used with profit. On such lands, howm pr, good crops of maize cannot be 

 expected to immediat'dly follow, as the celeal crops have a rather exhausting 

 effect on the soil. A ci'op of cowpeas for green manuring or for grazing 

 •with pigs would add nitrogen more cheaply and more profitably, and would 

 ensure a better maize or sorghum crop the following season. The writer has 

 in mind many of the upland soils of the South Coast, which- are used for 

 growing winter and summer fodder crops alternately and which are not as 

 fertile as the alluvial soils. A good rotation, which would maintain or improve 

 the soil fertility and enable heavier fodder crops to be grown, would be as 

 follows : — 



Wheat, or wheat and peas ... ... Sown in April. 



Cowpeas ... ... ^ ... ... Sown in November. 



" Maize, sorghum or Sudan grass ... Sown in October. 



This would give thi'ee fodder crops in two years and could be worked in 

 two paddocks, so that summer and wintei' fodders are grown each .season. 



Ort' the whole then, 1 cwt. superphosphate per acre can be thoroughly 

 recommended for winter green fodder crops on the coast. In an average' of 

 sixteen tests it has given an increase of 1 ton 1 cwt. per acre over the 

 unmanured plots. Thus, with an increase of I5s. 6d. in the value of the crop 

 as against a cost of 5s. 6d. for superphosphate, a net profit of 10s. per 

 acre has been made from the fertiliser. 



Southern Tablelands. 



Not many tests have yet been made with fertilisers for green winter 

 fodders on the Southern Tablelands, but the few that have been conducted 

 indicate that 2 cwt. superphosphate per acre is the best fertiliser. An 

 average increase of 3 tons 8 cwt, fodder per acre has been made, giving a 

 net profit of 40s. per acre. 



Effect of Subsoiling and Deep Tillage. 



T?EPORTiNG the results of extensive subsoiling experiments at twelve stations 

 in the Great Plains area of the United States over an average of five and a 

 half years, Messrs. E. C. Chilcott and J. S. Cole, in the Journal of 

 A ffr {cultural Research, Vol, xiv, No. II, show that subsoiling and deep 

 tilling have Ixjen of no value in overcoming drought. The eft'ect, on the 

 contraiy, apparently has been to reduce the yields in those seasons that are 

 below the average in production. Experiments have been coiiducted with 

 the subsoil plough, a deep tillage machine and dynamite, but the effect of 

 deep tillage appears to be essentially the sanH>, irresfK'ctive of the means by 

 which it is accompli,shed. "The quite normal popular belief in the efficiency 

 of deep tillage as a means of overcoming di-ought oi- of increasing yields has 

 little foundation of fact, but is based <m misconceptions and lack of know- 

 ledge of the form and extent of the root systems of plants, and of the 

 Jx'haviour and movement of water in the soil." 



