CARBON-NITROGEN RATIOS IN ORGANIC FERTILIZER MATERIALS IN RELATION TO THE AVAILABILITY OF THEIR NITROGEN

Abstract

34 organic ammoniates and waste organic materials were tested with regard to the availability of their N. Ratings, particularly of their insoluble N, were made of these materials by vegetative, nitrification, and permanganate methods. A study then was made of the applicability of the principle of the C-N ratio in explaining the estimated availability of their N. This principle proved to be a valuable supplemental aid in determining the quality of the contained N. In some cases, it was found necessary to apply a correction to the C-N ratio by eliminating the C of the lignin in the material. For certain materials, application of this correction factor failed to bring the products into line with the known availability of their N.