With the higher cost of nitrogen this spring and even higher cost for soymeal in the ration, getting the nitrogen right for your small grains is important.
Yield potential for small grains hinges on planting date and fall growth. This establishes the number of tillers, which establishes the yield potential for each field.
If the triticale was planted on time — 10 days to two weeks before wheat for grain — it maximizes the number and size of tillers. If sufficient nitrogen was available in the soil — from heavy manure applied before the previous summer crop, or up to 60 pounds of fall-applied nitrogen — the yield potential can increase 43% from increased size and number of tillers.
Our replicated research has found that on-time planting will pick up and store 60 to 120 pounds of nitrogen before winter, using the manure nitrogen still being released after the summer corn silage is harvested. If your triticale is 6 to 10 inches tall and thick at green-up, then you can assume the higher number and can subtract that from this spring’s topdress. I have found that fields like this have a potential yield of 3 to 4 tons of dry matter per acre.
Planting later, though, can have a profound effect and can drop yield potential by 35% or more. A crop that was planted at the same time or even later than the wheat planting date for your area will not have the tiller generation necessary for high yields.
A secondary effect is that the manure-released nitrogen left over from corn silage is wasted, as we have found that the late-planted winter forage only has time to take up 4 to 5 pounds of nitrogen instead of 60 to 120 pounds.
If your winter forage is only 3 to 4 inches or less at green-up, especially if you can see the rows in between, then you can realistically assume 2 to 2.5 tons of dry matter per acre and should fertilize for that.
Use caution with manure
For those who think they can topdress manure to supply nitrogen, they are mistaken. Unless it rains immediately after spreading, it will only supply about 2 to 3 pounds of nitrogen per 1,000 gallons of manure topdressed.
This is because the ammonia will react with enzymes on the vegetation and split it off as ammonia gas, which then volatilizes. The organic fraction of the manure left on the vegetation will need time to decay, and being that it’s on the surface, it is only 85% used up by the crop.
If the winter forage is harvested before spring warmth allows much of those organics to break down, any manure remaining in and harvested with the crop can pollute the silage.
Tips for N application
If you’re applying nitrogen and sulfur, remember that sulfur needs to be a minimum of 1 pound for every 10 pounds of nitrogen.
After the crop starts spring growth, it will take around eight weeks to reach harvest stage. We don’t recommend split nitrogen unless the rates of nitrogen and sulfur are high enough to burn the leaves of the crop.
And a word of caution for those pushing for higher crude protein to offset high soymeal prices. If you have prolonged dry spells followed by rain just before harvest, be sure to do a safety check for nitrate accumulation. Many different plants can accumulate nitrate under the right weather conditions.
The low cost of a nitrate test allows you to feed with confidence. This is especially true if you forgot or did not apply sufficient sulfur or were short on magnesium, so the plant cannot convert nitrate to usable protein.
A shortage of these critical elements, not high nitrogen rates, are the basis of many nitrate issues.
Kilcer is a certified crop adviser in Kinderhook, N.Y.