. Manures and fertilizers; a text-book for college students and a work of reference for all interested in the scientific aspects of modern farming . um sulfate. 3. Leather. 4. Dried blood. 5. Nitrate of soda. Same amounts of pot-ash, phosphoric acid, and nitrogen used in each case. Sameas Fig. 9, except for the omission of lime. (5) None of the fertilizers should be applied until spring,in order to avoid possible loss during the winter. (6) In case a substance contains some other fertilizeringredients than nitrogen, care must be taken, by the addi-tion of an assured excess of all of them, to e
. Manures and fertilizers; a text-book for college students and a work of reference for all interested in the scientific aspects of modern farming . um sulfate. 3. Leather. 4. Dried blood. 5. Nitrate of soda. Same amounts of pot-ash, phosphoric acid, and nitrogen used in each case. Sameas Fig. 9, except for the omission of lime. (5) None of the fertilizers should be applied until spring,in order to avoid possible loss during the winter. (6) In case a substance contains some other fertilizeringredients than nitrogen, care must be taken, by the addi-tion of an assured excess of all of them, to eliminate thepossibility of their having influenced the result. 118 FERTILIZERS (7) All of the lots of soil must receive even slightlymore of all the necessary fertilizers, other than nitrogen,than are necessary to the production of a maximum crop. (8) Less nitrogen should be used in all cases than isnecessary to the production of a maximum crop, in orderthat the best forms may exert their full effect. (9) In order to make sure that the conditions under (7)and (8) have been surely met, nitrogen must be appliedin at least two different 12 3 4 5 6 Fig. 9. — Barley, Limed (except 1). 1. No nitrogen, no lime. 2. No nitrogen. 3. Ammonium Leather. 5. Dried blood. 6. Nitrate of soda. All received likeamounts of potash, phosphoric acid, and nitrogen. Like Fig. 8, exceptingthat lime was used for all but No. 1. (10) The nitrogen content of the soil which is selectedshould be so low that fairly large applications of nitrogenmay be made, for the accuracy of the results will be in-creased thereby. (11) One should use relatively larger amounts of theless available substances than of the more active ones, inorder that the experimental error may be made as nearlyalike in all cases as possible. (12) The experiments should be conducted on land THE AVAILABILITY OF ORGANIC NITROGEN 119 in its natural condition, as well as in pots ; since the formerprovides against any possibl
Size: 2411px × 1036px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectfertili, bookyear1913
