Wheat Management for Fall 2021

This year winter wheat yields were very high, averaging 103 bu/acre across five locations in our Ohio Wheat Performance Test (https://ohiocroptest.cfaes.osu.edu/wheattrials/). For comparison, the average wheat yield was 94 bu/acre in 2020 and 86 bu/acre in 2019. High yields were likely due to a long grain-fill period coupled with timely moisture, enhancing grain fill without leading to head scab or other diseases. Many of us would like to repeat these high-yielding conditions next year, but much was weather-dependent. However, good fall management sets up the crop to take advantage of a good year, particularly since fall tillers contribute the most to yield.

Here are some management tips to keep in mind for fall 2021:

  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 that are highly susceptible to Fusarium head scab, also known as head scab, as fungicides alone will not provide adequate protection again head scab and vomitoxin. There are high-yielding varieties with very good scab resistance. Plant seed that has been properly cleaned to remove shriveled kernels and treated with a fungicide seed treatment to control seed-borne diseases. The 2021 Ohio Wheat Performance Test results can be found at: https://ohiocroptest.cfaes.osu.edu/wheattrials/
  2. Optimum seeding rates are between 1.2 and 1.6 million seeds/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 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-most 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. This disease is most damaging when plants are infected by the virus in the fall. The best time to plant is within 10 days after the Fly Safe Date (Figure 1).  
  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 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. Follow the Tri-State Fertilizer Recommendations for Corn, Soybeans, Wheat, and Alfalfa (https://agcrops.osu.edu/FertilityResources/tri-state_info). Apply 20 to 30 lb 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 30-50 ppm (Mehlich-3 P) for optimum production (Table 1). Do not add any phosphorus if soil test levels are higher than 50 ppm.

Table 1. Wheat Phosphorus Recommendations from the Tri-State Fertilizer Recommendations for Corn, Soybeans, Wheat, and Alfalfa.

 

Wheat Yield Potential (bu/acre)

 

60

90

120

150

Mehlich-3 P (ppm)

---------------------------------------lb P2O5/acre---------------------------------------

10

130

145

160

175

20

80

95

110

125

30-50

30

45

60

75

>50

0

0

0

0

Soil potassium should be maintained at levels of 100-130 and 120-170 ppm (Mehlich-3 K) on sandy soils (CEC < 5 meq/100 g) and loam/clay soils (CEC > 5 meq/100 g), respectively. If potassium levels are low, apply K2O fertilizer at planting, depending on soil CEC and yield potential (Table 2).

Table 2. Wheat Potassium Recommendations from the Tri-State Fertilizer Recommendations for Corn, Soybeans, Wheat, and Alfalfa.

 

 

Wheat Yield Potential (bu/acre)

Soil CEC

Mehlich-3 K (ppm)

60

90

120

150

 

 

lb K2O/acre

Sands

50

100

105

115

120

(<5 meq/100 g)

75

65

75

80

90

 

100-130

35

45

50

60

 

>130

0

0

0

0

Loams and Clays

50

160

165

175

180

(>5 meq/100 g)

75

115

120

130

135

 

100

70

80

85

95

 

120-170

35

45

50

60

 

>170

0

0

0

0

Soil pH should be between 6.3 and 7.0. In Ohio, limed soils usually have adequate calcium and magnesium.

  1. For no-till wheat, select burndown herbicides to control existing weeds prior to planting. For more information on herbicide options, see: https://agcrops.osu.edu/newsletter/corn-newsletter/2020-30/burndown-herbicides-no-till-wheat

Crop Observation and Recommendation Network

C.O.R.N. Newsletter is a summary of crop observations, related information, and appropriate recommendations for Ohio crop producers and industry. C.O.R.N. Newsletter is produced by the Ohio State University Extension Agronomy Team, state specialists at The Ohio State University and the Ohio Agricultural Research and Development Center (OARDC). C.O.R.N. Newsletter questions are directed to Extension and OARDC state specialists and associates at Ohio State.