April, 1940] PASTURE TOP-DRESSING IN N. H. 23 



the season and can afford to use nitrogenous fertilizers on their pas- 

 tures. Others have all the feed they need in the spring and early 

 summer, and if so, they should fertilize, if possible, to increase mid- 

 summer feed. Delayed applications of nitrogen to accomplish this 

 end have not been thoroughly investigated but such tests are in 

 progress. On the heavier soils, however, the use of superphosphate, 

 potash and lime to encourage the growth of wild white clover has 

 been found to increase midsummer forage production, since clover 

 grows better than the grasses in hot weather. 



Different nitrogen carriers have been under test for a number of 

 years on Seavey and Livingston pastures. The carrier that has giv- 

 en the greatest response on Seavey gave the least on Livingston pas- 

 ture, hence no definite recommendations can be made. This apparent 

 discrepancy is doubtless due to complex soil factors. In considering 

 nitrogen carriers, however, it should be borne in mind that sulphate 

 of ammonia tends to make the soil more acid, whereas the other 

 nitrogen carriers are neutral or alkaline and apparently reduce the 

 need for separate lime applications. 



A heavy triennial application of superphosphate on Seavey pas- 

 ture has given better returns over a period of years than a light 

 annual one, with equal amounts of phosphoric acid applied. With 

 potash, the annual light treatment has been superior to a heavy tri- 

 ennial one. 



The pastures under test yielded about 1300 pounds more dry mat- 

 ter per acre in the wet season of 1938 than in the dry season of 1939 

 with the same treatments. This suggests that moisture is an im- 

 portant limiting factor in pasture production and emphasizes the 

 necessity of choosing a heavy, well watered soil for treatment. 



As an average, one dollar invested in fertilizers used in these pas- 

 tures has brought in about two dollars' worth of feed. Such a re- 

 turn appears to be ample to warrant the use of this method of im- 

 proving the income on dairy farms. Kind of soil, rate of application 

 and choice of materials are factors that will influence the economy 

 of fertilizer usage. 



The chief reason for low carrying capacity of New Hampshire 

 pastures is lack of fertility. Restoring this fertility with fertilizer 

 and lime will improve the feed and increase the carrying capacity of 

 the pasture so that a farmer can confine his improvement work to 

 a small part of his pasture acreage. Mapping out a definite fertil- 

 izer and lime schedule over a period of years will solve the pasture 

 prolDlem on many farms. Such a system should not involve the 

 treatment of more than one and one-half to two acres of land for 

 each animal unit on the farm. 



Reasonable amounts of materials to apply are : one ton of lime 

 l^er acre every five or eight years ; 200-300 pounds of 47 per cent or 

 500-700 pounds of 20 per cent superphosphate every third or fourth 

 year ; 100-200 pounds of 60 per cent of muriate potash every third or 

 fourth year or in divided applications, and 150-250 pounds of one of 

 the nitrogen carriers annually. 



If complete fertilizers are to be used, annual applications are pref- 

 erable in amounts approximating 200 to 400 pounds of an 8-16-16 



