April, 1940] PASTURE TOP-DRESSING IN N. H. 21 



Top-Dressing Increases Protein 



The protein content of the dry matter of the forage has been in- 

 creased in this top-dressing work, no matter what the treatment. 

 Table 21 states the percentage protein found in the different treat- 

 ments of Seavey and Livingston pastures. The higher average pro- 

 tein of Livingston pasture as compared with Seavey probably 

 reflects the greater percentage of clover that develops there, par- 

 ticularly under the PK treatment. These data are presented merely 

 to indicate that dry matter alone is not an adequate criterion to 

 determine feeding value. 



Table 21. — Per cent protein in dry matter of forage 



Furthermore, this protein increase undoubtedly favorably affects 

 the palatability of the grass and accounts for the cows spending a 

 greater amount of time feeding on treated than on untreated pas- 

 ture, if they have a choice. 



Another factor which doubtless has a bearing on the nutritional 

 value of treated pasture grass is the increased mineral content. 

 While the forage on these trials was not analyzed for its mineral 

 content, such work has been done by a number of investigators. 

 For example, Brown^ reports, "The proportion of phosphorus (in the 

 forage) was raised about 60 per cent, as an average for two years 

 by an application of superphosphate. Potash treatments increased 

 the amount of potassium in eleven of twelve comparisons. Calcium 

 was increased apparently because of the prevalence of clover in the 

 LP and LPK plots, while the omission of superphosphate in the LK 

 plot resulted in a low percentage of calcium in the grasses present. 

 Clover in the NPK plot also had a low percentage of calcium. Su- 

 perphosphate alone increased calcium in clover and grasses as well. 

 Magnesium varied directly with calcium while manganese in the for- 

 age was reduced I)}- lime applications." 



It is impossible to evaluate the effect of the increased mineral con- 

 tent of pasture herbage due to fertilization. That minerals are im- 

 portant no one can deny and the fact that most grain mixtures carry 

 calcium and phosphorus in the form of limestone and bone meal is 

 evidence of their need. Furthermore, it is generally conceded that 

 these minerals in organic substance, such as pasture herbage, are 

 more effective in animal nutrition than they are in other forms. 

 This appears to lend much weight to the necessity of supplying min- 

 erals to infertile pastures to enhance the mineral value of the rough- 

 iige itself. 



^B. A. Brown, Am. Soc. Agron. Journal. Vol. 24. No. 2, February. 1932, 



