Table 1.2-8. Residual nitrogen contribution from legumes1

Previous crop Percent Stand High-productivity fields Moderate-productivity fields Low-productivity fields
  Soil productivity group2 1 Soil productivity groups2 2 & 3 Soil productivity groups2 4 & 5
  Nitrogen credit (lb/A)
  1. When a previous legume crop is checked on the Penn State soil test information sheet, the residual nitrogen for the year following the legume is calculated and given on the report. This credit should be deducted from the N recommendation given on the soil test report.
  2. See table 1.1-1 in the basic soils section for information on soil productivity groups.
First year after alfalfa >50%
25-49%
<25%		 120
80
40		 110
70
40		 80
60
40
First year after clover or trefoil >50%
25-49%
<25%		 90
60
40		 80
60
40		 60
50
40
First year after soybeans harvested for grain.   ---- 1 lb N/bu soybeans ----