Wheat Harvest and Double Crop Considerations for 2024

Originally Published in the C.O.R.N. Newsletter

Authors: Laura Lindsey, Osler Ortez

Winter wheat maturation is about 10-14 days ahead of normal with harvest beginning late last week in southern Ohio. Last year, winter wheat yield was extremely high with a state average of 90 bu./acre (USDA NASS, 2024). During the previous five years, the state average wheat yield ranged from 56 to 85 bu./acre (average of 73 bu./acre). Last year, we attributed high yields to low rainfall (and consequently low disease) and cool temperatures, leading to a long grain-fill period. This year, we’ve experienced warmer temperatures, greater disease, and shorter grain-fill periods. Between March 1 and June 16, 2024, there were 1,000, 1,135, and 912 growing degree days at the Northwest Agricultural Research Station, Western Agricultural Research Station, and Wooster Campus, respectively (Table 1). During the same time period last year, there were 738, 816, and 617 growing degree days at the Northwest Agricultural Research Station, Western Agricultural Research Station, and Wooster Campus, respectively.

Table 1. Monthly growing degree day accumulation in 2023 and 2024 (CFAES Weather System, https://weather.cfaes.osu.edu/).

	Northwest Agricultural Research Station (Wood County)
	2023	2024
March	4	44
April	134	127
May	339	505
June 1-16	261	324
TOTAL	738	1,000
	Western Agricultural Research Station (Clark County)
March	13	55
April	151	231
May	382	535
June 1-16	270	314
TOTAL	816	1,135
	Wooster Campus (Wayne County)
March	10	29
April	128	182
May	281	438
June 1-16	198	263
TOTAL	617	912

This year, wheat yield will likely be lower than last year. However, earlier wheat harvest opens opportunities for a second crop following wheat. In Ohio, double-crop soybeans are the most common crop after wheat harvest, but other crops, such as sunflower, may be planted. The two primary requirements for successful double cropping are: 1) There must be time for the production of a second crop, and 2) There must be adequate water to produce two crops, whether from stored soil moisture, rainfall, or irrigation. The first requirement will likely be met, with earlier wheat harvest and a predicted later first freeze date, but continued dry weather in areas of the state may be problematic. However, several management practices will help maximize double crop yield potential.

Double crop soybean management considerations.

1. Soybean relative maturity. Relative maturity (RM) has little effect on yield when soybeans are planted during the first three weeks of May. However, the effect of RM can be larger for late plantings. When planting soybean late, the latest maturing variety that will reach physiological maturity before the first killing frost is recommended. This is to allow the soybean plants to grow vegetatively as long as possible to produce nodes where pods can form before vegetative growth is slowed due to flowering and pod formation.

Table 2. Recommended relative maturity (RM) ranges for soybean varieties planted in June and July in northern, central, and southern Ohio.

Region	Planting Date	Suitable RM
Northern Ohio	June 1-15	3.2-3.8
	June 15-30	3.1-3.5
	July 1-10	3.0-3.3
Central Ohio	June 1-15	3.4-4.0
	June 15-30	3.3-3.7
	July 1-10	3.2-3.5
Southern Ohio	June 1-15	3.6-4.2
	June 15-30	3.5-3.9
	July 1-10	3.4-3.7

1. Row spacing. Double-crop soybeans should be produced in narrow rows- 7.5 or 15-inch row spacing. The later soybeans are planted, the greater the yield increase due to narrow rows. Soybeans grown in narrow rows produce more grain because they capture more sunlight energy, which drives photosynthesis.

1. Seeding rate. Soybean plant population at harvest for mid-to-late June plantings should be between 130,000-150,000 plants/acre. The harvest population for early July plantings should be greater than 180,000 plants/acre. Harvest population is a function of seeding rate, quality of the planter operation, and seed germination percentage and depends on such things as soil moisture condition, seed-soil contact, and disease pressure.

Double-crop sunflower management considerations.

In addition to double cropping with soybean, other alternatives may become feasible within the crop system. In 2022-2023, field experiments were established to study sunflowers’ viability as a double crop after wheat or barley harvest in Ohio (Figure 2).

Figure 2. Double crop agronomic sunflowers planted at 30-inch row spacing after wheat harvest during 2022-2023 field projects in Ohio.

The study had three commercial high oleic sunflower varieties: “ultra-early” maturity (N4H161 CL), “early” maturity (N4H302 E), and “mid-early” maturity (CP 455 E). These varieties were studied across three seeding rates: 17,000 seeds per Acre, 22,000 seeds per Acre, and 27,000 seeds per Acre. Preliminary results showed sunflower yields ranging between 1,012 lbs./Ac and 2,740 lbs./Ac (Table 3). The average yields per site were in the 1,400 to 1,900 lbs./Ac range, with the two highest yield sites being comparable to the average U.S. sunflower seed yields in the past two years.

Table 3. Study locations, previous crop, planting dates, harvest dates, and double crop sunflower yields in pounds per Acre (lbs./Ac) at 10% moisture.

Study Location	Previous Crop	Planting Date	Harvest Date	Minimum Yield	Average Yield	Maximum Yield
Northwest, Wood County	Barley	6/29/2022	11/18/2022	1,296 lbs/Ac	1,867 lbs/Ac	2,599 lbs/Ac
Western, Clark County	Wheat	7/11/2022	11/10/2022	1,012 lbs/Ac	1,967 lbs/Ac	2,740 lbs/Ac
Wooster, Wayne County	Wheat	7/15/2022	12/21/2022	1,003 lbs/Ac	1,464 Lbs/Ac	1,897 Lbs/Ac

From the preliminary results on the sunflower work, crop production challenges have included weather, equipment availability, bird damage, plant lodging, and variable/low stand counts which have possibly limiting crop yields. This project is in progress and will be planted again in 2024, more results are forthcoming. Future considerations for sunflowers should include consistency of results across sites/years, variety selection, seeding rate, germination, fertility, bird control, seed/oil quality, and marketing options as major priorities.

Reference:

United States Department of Agriculture (USDA) National Agricultural Statistics Service (NASS) 2024. Quick Stats. Available at: https://quickstats.nass.usda.gov/results/58FEB025-0AD4-3B92-9F18-30D377D14279

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.

Author(s):

Laura Lindsey, Osler Ortez