Abstract
Availability of ammonium chloride supplied by crops was examined on several soils with regard to their ammonium fixing power. It was obserbed, in general, that rice or wheat plants were able to utilize more ammonium from a soil which has weaker fixing power than from the one with stronger fixing power. But a part of fixed ammonium was recovered by crops, and the degree of its availability was seemed to be depended upon natures of the fixing minerals.
