By Laura Lindsey, Pierce Paul and Ed Lentz
COLUMBUS — Wheat helps reduce problems associated with the continuous planting of soybean and corn and provides an ideal time to apply fertilizer in July/August after harvest. With soybean harvest around the corner, we would like to remind farmers of a few management decisions that are important for a successful crop.
For additional information on winter wheat management, download a free pdf of the Ohio Agronomy Guide here.
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1. Select high-yielding varieties with high test weight, good straw strength, and adequate disease resistance. Do not jeopardize your investment by planting anything but the best yielding varieties that also have resistance to the important diseases in your area. Depending on your area of the state, you may need good resistance to powdery mildew, Stagonospora leaf blotch, and/or leaf rust.
Avoid varieties with susceptibility to Fusarium head scab. Plant seed that has been properly cleaned to remove shriveled kernels and treated with a fungicide seed treatment to control seed-borne diseases.
The 2018 Ohio Wheat Performance Test results can be found here.
2. Optimum seeding rates are between 1.2 and 1.6 million seeds per acre. For drills with 7.5-inch row spacing, this is about 18 to 24 seeds per foot of row. When wheat is planted on time, actual seeding rate has little effect on yield, but high seeding rates (above 30 seeds per foot of row) increase lodging and the risk of severe powdery mildew development next spring.
3. Plant after the Hessian Fly Safe Date for your county. This date varies between September 22 for northern counties and October 5 for southern-most counties. Planting before the Fly Safe Date increases the risk of insect and disease problems including Hessian Fly and aphids carrying Barley Yellow Dwarf Virus. The best time to plant is within 10 days after the Fly Safe Date (click here for fly safe map). Fall wheat growth is reduced when planting is delayed resulting in reduced winter hardiness. If planting is delayed until the third or fourth week after the fly-safe date, plant 1.6 to 2.0 million seeds per acre (24 to 30 seeds per foot of row).
4. Planting depth is critical for tiller development and winter survival. Plant seed 1.5 inches deep and make sure planting depth is uniform across the field. No-till wheat seeded into soybean stubble is ideal, but make sure the soybean residue is uniformly spread over the surface of the ground. Shallow planting is the main cause of low tiller numbers and poor over-winter survival due to heaving and freezing injury. Remember, you cannot compensate for a poor planting job by planting more seeds; it just costs more money.
5. Apply 20 to 30 pounds of actual nitrogen per acre at planting to promote fall tiller development. A soil test should be completed to determine phosphorus and potassium needs. Wheat requires more phosphorus than corn or soybean, and soil test levels should be maintained between 25-40 ppm for optimum production.
If the soil test indicates less than 25 ppm, then apply 80 to 100 pounds of P2O5 at planting, depending on yield potential. Do not add any phosphorus if soil test levels are higher than 50 ppm. Soil potassium should be maintained at levels of 100, 120, and 140 ppm for soils with cation exchange capacities of 10, 20, or 30 meq, respectively. If potassium levels are low, apply 100-200 pounds of K2O at planting, depending on soil CEC and yield potential.
Soil pH should be between 6.3 and 7.0. In Ohio, limed soils usually have adequate calcium and magnesium. Sulfur should be added in the spring to sandy soils and soils with low organic matter.
Ohio research from the past four years has not shown a yield response to supplemental sulfur on medium to fine-textured soils that have adequate organic matter. The key to a successful wheat crop is adequate and timely management.
(This information was originally published in the Ohio State University C.O.R.N. (Crop Observation and Recommendation Network) newsletter, by OSU Extension State Specialist, Soybean and Small Grains Pierce Paul; OSU Extension State Specialist Corn and Wheat Diseases Ed Lentz, and CCA (Hancock County Extension Educator)
