Browse on keywords: fertility nitrogen soil testing
Search results on 10/23/18
7951. Sims, J.R. and G.D. Jackson. 1971. Rapid analysis of soil nitrate with chromotropic acid.. Soil Sci. Soc. Am. Proc. 3:603-606.
9690. Malhi, S.S., M. Nyborg, D.R. Walker and D.H. Laverty. 1984. Fall and spring soil sampling for mineral N in northcentral Alberta.. Can. J. Soil Science 65:339-346..
The timing of soil sampling for mineral N was investigated by sampling in fall and in spring from the 0-30 cm depth in 100 field experiments. On the average of the 100 experiments, the NO3-N in soil increased from 16 kg N/ha in the fall to 34 kg N/ha in spring and the mineral N in soil increased from 28 kg N/acre in fall to 49 kg N/ha in spring. Soil test programs in the Prairie Provinces are based primarily on field experiments with only spring sampling, while farm smapling is mostly conducted in the fall. At least in north-central Alberta, fall sampling for soil test for NO3-N should be restricted to the late fall and probably an adjustment to N recommendations should be made for the smaller amounts of NO3-N found in fall rather than spring.