370 TRANSACTIONS OP SECTION M. 



produce secured. Thus, in these Cockle Park experimente, on the average 

 of 21 years, if quantity alone be regarded, sulphate of ammonia used by itself 

 has involved an annual loss of 6s. 4rf. per acre, whereas, if the reduced quality 

 of the hay be taken into account, the loss is increased to 15s. 7d. per acre. On 

 the other hand, a quantitative gain of 4.s. 2d. per acre per annum from the use 

 of phosphate and potash is raised to one of 32.S. 5rf. owing to the superior 

 quality of the hay. While there is a certain relationship between the chemical 

 composition, the botanical analysis and the feeding value of the hay there will 

 probably be general agreement with Middleton when he says that ' Without 

 an appeal to the animal the relative values of samples grown under different 

 treatm.ent cannot be measured.' In my view this form of research may, with 

 advantage, be largely extended. 



It is unnecessary to attempt to abstract the numerous permanent hay experi- 

 ments which have been a prominent feature of field-plot trials, especially 

 during the past thirty years. These show unmistakably that farmers of 

 meadow land have an attractive opportunity for the judiciou-s expenditure of 

 capital on artificial manures. It is an opportunity which most progressive 

 farmers have embraced, though the condition of wide areas of meadow land 

 shows how much still remains to be accomplished. Broadly speaking, phosphates 

 are the foundation on which manurial improvement is most surely laid, supple- 

 mented in most cases by nitrogen, and in many cases by potash. There are 

 numerous instances throughout the country of phosphates alone producing the 

 maximum return in profit and quality, and sometimes even in weight. Thus 

 on a field in East Suffolk, ' of very poor, heavy land that had been untenanted 

 for some years at Rendham and apparently grew nothing but wild carrots and 

 a little rough grass,''* quarter-acre plots were laid down in the autumn of 

 1900. ' The hay crop of 1901 was so poor that it was not considered worth 

 weighing.' But in the subsequent five years the results were very remarkable, 

 the average yield on the unmanured area being 8 cwt. of hay, as contrasted 

 with 35 cwt. on the plot which received a single dressing of 10 cwt. of basic 

 slag. Taking hay at 21. per ton, and therefore making no allowance for the 

 superior quality of the produce, or for residues, the slag gave a return, after 

 deducting its cost, of 12?. per acre.'' But the apparent lack of the need of 

 phosphates for support from added nitrogen is usually associated with the 

 earlier years of such experiments, and such need disappears later. Hall accounts 

 for the superior early action of the phosphate as follows : ' It is not uncommon 

 to find cases where the application to grass land of a phosphatic manure, like 

 super-phosphate or basic slag, is followed by a great increase of crop, the 

 addition of the phosphoric acid to the dormant nitrogen and potash in the 

 soil having supplied the missing element in a complete plant food. ... A 

 nitrogenous manure alone is often thought exhausting, but probably a phosphatic 

 manure used singly will even more quickly impoverish the soil.' ^° I agree that 

 this argument applies to tillage land growing non-leguminous crops, but it 

 seems to be put too strongly in the case of permanent grass land. In my view 

 the more marked effects of phosphates in the earlier years is due to the fact 

 that when one applies phosphates one is indirectly applying nitrogen as well. 

 But after the first great flush of clovers, and of Leguminosse generally, this 

 class of plant becomes less abundant, and consequently the fixation of atmospheric 

 nitrogen by the herbage is reduced, and the crop requires and responds to 

 nitrogenous manures. Where, however, there are abundant natural supplies 

 of potash in the soil the stage of marked reduction in fertility of a hay field 

 may be long delayed. Thus on Palace Leas, at Cockle Park, the plot which 

 for over twenty years has annually received nothing but phosphates is showing 

 a larger increase in the hay crop on the average of the last five years than it 

 did on the average of the first five. And not only so, but the addition of 



" Report, East Sujfolh County Council, ' Field Experiments, How very 

 poor heavy land Pasture may be improved.' 



'' Cambridge University Department of Agriculture, ' Guide to Experi- 

 ments,' 1907, p. 150. 



2" A. D. Hall, ' The Manuring of Grass Land,' Jour. Roy. Agric. Soc. Engl., 

 1903, p. 76. 



