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Rate of Application. 



As to the rate at which manure should be applied no fixed rules can 

 be given. The rate will depend upon the character of the soil, the 

 quality of the manure, the nature of the crop, and the frequency of 

 application. Cold moist soils should be manured lightly and often. 

 Thaer, a German writer, states 17 to 18 tons per acre to be an abun- 

 dant application, 14 tons good, and 8 to 9 light ; other German writers 

 consider 7 to 10 tons light, 12 to 18 tons usual, 20 tons or more heavy, 

 and 30 tons very heavy, Stephens suggests 8 to 12 tons for roots and 

 15 to 20 tons supplemented by commercial fertilisers for potatoes. Sir 

 Henry Gilbert considers 14 tons per acre annually excessive for wheat 

 and barley. In New England the rate varies from 6 to 12 tons. 

 Twenty tons is a frequent application in New Jersey, as well as mother 

 regions where truck farming is practised. As a general rule it is more 

 scientific to apply small amounts of manure freguently than to apply 

 large amounts at longer intervals. 



COMBINING BARNYARD MANURE WITH OTHER FERTILISING MATERIALS. 



It has been the general experience that probably the best way to 

 utilise barnyard manure is in combination with such materials as sup- 

 plement and conserve its fertilising constituents. It has already been 

 pointed out how certain substances, such as kainit and superphosphate, 

 which possess a high fertilising value, may also be used to advantage 

 as preservatives on account of their ability to check fermentation or to 

 fix ammonia. Even the limited extent to which it is necessary to use 

 these materials in the stable will improve the fertilising value of the 

 manure, but it is necessary to do more than this if a well-balanced 

 fertiliser is desired, for, as has been shown, barnyard manure con- 

 sidered simply as a supplier of nitrogen, phosphoric acid, and potash 

 is comparatively poor. It has been shown that the proportions of 

 potash and phosphoric acid especially are low. The potash, however, 

 is in a very available form and does not need to be reinforced to the 

 same extent as the much less available phosphoric acid. 



Although nitrogen is the constituent most abundant in manure it 

 has been found that in order to get the best results in general it should 

 be reinforced if prompt action is desired. This is explained by the fact 

 that a large part of the nitrogen of manure is very slowly available. 

 Sir Henry Gilbert says on this point : 



The nitrogen of farmyard manure must obviously exist in very different condi- 

 tions. That due to the urine of animals will be most rapidly available, that in the 

 finely divided matter in the feces will be much more slowly available, and that in 

 the litter still more slowly available. Hence, the small proportion that is at once 

 effective and th.6 very large amount that accumulates within the soil in a very 

 slowly available condition. 



Experiments at Rothamsted indicate that the nitrogen of barnyard 

 manure is not half as valuable, weight for weight, as that of sulphate 

 of ammonia. 



What has been said about supplementing barnyard manure with 

 more concentrated fertilising materials should not be taken to imply 

 that the two- kinds of fertilisers- should necessarily be composted or 

 applied at the same time. It may be desirable to apply the manure at 



