The dry-matter content of field-cured and green forage
1916
Arny, A.C.
The alfalfa and the timothy and clover mixed from a large number of plots, when field cured under canvas cock covers, in 1914, were less variable in dry-matter content than the product of the same number of plots weighed as soon as cut in 1915. The white sweet clover was more variable in dry-matter content when weighed and sampled in the field-cured condition than when weighed and sampled as soon as cut. Basing the weights of the product of the different plots on the field-cured hay gave a closer aproximation of the correct weights of alfalfa and of timothy and clover mixed than weighing these crops as soon as cut. The green weights of the white sweet clover gave a closer approximation of the correct weights of the product of thedifferent plots than the field-cured weights. When cut at the stages of maturity mentioned previously in this article, white sweet clover has a higher moisture content than alfalfa or timothy and clover mixed. Therefore, sweet clover is not as easily field cured properly as alfalfa or timothy and clover mixed and securing a repesentative sample from it in this condition for dry matter determination is a more difficult task. A variation of 5 percent or more in the moisture content of the product from experimental plots is too great for reasonably accurate work. Therefore, it is not good practice to base weights of forage crops upon experimental plots on field cured weights or green weights. Samples for making corrections of yields on the air-dry or on the water-free basis are necessary for accurate work. Where samples of the product of different plots are taken for making corrections of yields on the air-dry or moisture-free basis, weighing the product of each plot as soon as cut has proved to be the more desirable method of the two. This method is especially desirable where nitrogen determination or complete analysis is to follow the determination of dry-matter content.
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