Ag Tips from JJ: April 10

Brought to you by: Jonah T. Johnson, MS, CPAg, CCA - Sales Agronomist, PCT | Sunrise
April 10, 2019: Still questioning your winter wheat stands? 
To destroy or not to destroy, that can be a challenging question. Numerous inquiries have come on whether or not to proceed with managing thin wheat stands for yield. Over the years, I have seen really thin stands perform respectfully well. Wheat is surprisingly a very resilient crop.
 
However, if you have large holes within fields that are completely missing stands, then those are easier candidates to terminate and transition to soybeans or corn. Sometimes wheat stands in linear rows can be deceiving, especially when there is brown tissue within the row. Be sure to take adequate stand counts to quantify your yield potential and to determine the best course of action.


Consider the following:
  1. Measure three (3) feet of row and count the number of plants
  2. Multiply number of plants by four (4) and then divide that number by row spacing in inches (e.g. 7.5 inch row-width spacing).
Example: 30 plants in 3 feet of row multiplied by 4. Then divide by the 7.5 inch row width. This equals 16 plants per square foot.

Yield Estimates:
  • 22+ plants = 100% potential
  • 18+ plants = 90%
  • 15+ plants = 75%
  • 12+ plants = 60%
Wheat typically can keep the main stem and four tillers per plant. When you have greater than four tillers per plant, wheat plants typically will contain smaller wheat heads with fewer spikelets (3 -4 kernels per spikelet) per head, which usually contains smaller grain kernels.
 
If you have adequate plants stands, in a somewhat uniform distribution across the field, then proceed to count tillers. When counting tillers, avoid counting the main stem.
  • If you count 70 or more tillers in the square foot area, you have an adequate number and can delay nitrogen application closer to the Feekes growth stage six, also known as jointing, or when the wheat head has emerged above the soil line, still inside the plant.
  • If you count less than 70 tillers in the samples area, but have adequate plants, an earlier application of nitrogen is suggested at green-up to stimulate tiller development.
    • In northern latitudes in Ohio, this may be more relevant, as wheat is finally greening.
    • Wheat in southern latitudes of Ohio have been greening up, and in most cases, patiently awaiting a nitrogen application.
    • Total nitrogen application per crop year should not exceed 130 total pounds. This would include any nitrogen applied in the fall to initiate tillering.
    • If you find your yield potential is lower than anticipated, but worth keeping, consider applying fewer pounds of total N.

Nitrogen Recommendations for Wheat

Yield Potential
(bu/ac)
Nitrogen Rate
(lb/ac)
60 60
70 75
80 90
90 110
100 130