ISSUE 6 June 8, 2000
N FOR YIELD AND/OR PROTEIN ENHANCEMENT OF SMALL GRAINS
Additional N can be foliar applied to small grains for yield
enhancement up to the 5 leaf stage of wheat. Beyond the 5 leaf stage, additional N
contributes to higher protein, but not to yield. Research at Carrington and Minot within
the last six years have shown that a post-anthesis application at the watery ripe stage of
kernel development is most effective in enhancing protein. The degree of burn due to the
application of N solutions is dependent on the temperature, plant stress, moisture
on the leaves, rate of N and dilution of product. The best conditions are cool, damp
leaves, low N rates and high dilution with water. Generally, a rate of 30 lb N/acre (about
10 gallon of 28%N solutions) has increased protein levels from 0.5 to 1%. Do not expect
greater increases with higher N rates. Also, dilute the solution 1/1 with water. Apply
when it is relatively cool, avoiding hot afternoons.
S FOR CANOLA RESCUE
Research at Langdon has indicated that application of sulfur
fertilizer solutions with any herbicide with an oil adjuvant is not recommended due to
excessive burn. The use of ammonium thiosulfate in particular (12-0-0-27S) is only
possible in canola due to the waxy cuticle it develops after the 5 leaf stage. The oil
breaks down the cuticle and would result in severe burns if AMTHIO was applied.
Application of the sulfur first, then the herbicide after a few days would be appropriate.
Remember
that S application will only increase yields postemergence if the S is applied before
bolting. Do not apply S even as an experiment during flowering.
Dr. Dave Franzen
NDSU Extension Soil Specialist