Traditional doublecrop options after wheat grown for grain have been soybean, sorghum, or sunflower. Doublecropping after wheat is a fairly common practice in central and eastern Kansas where rainfall often occurs toward the end of the summer and the growing season can be long enough to produce grain from these crops. However, with the shortage of forages from the extreme drought the last two years, producers may consider planting a forage crop or cover crop that can be used for forage instead of a grain crop.
Soybean has been the most popular doublecrop option in Kansas, largely because glyphosateresistant varieties made weed control easy. However, the cost of weed control has risen in recent years in areas where glyphosate-resistant weeds are present.
Although doublecrop soybean are normally harvested as a grain crop, it also can have value as a forage crop if necessary. As a legume, soybean makes a high-protein feed. Cattle can utilize soybean as either a hay or grazing crop, although there are limitations to both uses. If doublecrop soybean produces enough growth for a hay crop, it likely has had good enough weather to make a profitable grain harvest. Doublecrop soybean is not very conducive for grazing. It often is upright in growth and the stem will break easy if cattle open-graze a field, thus potentially wasting much of the forage. Strip grazing failed doublecrop soybeans will increase its utilization.
Although not ideal as forage it can be used that way if weather conditions are such that a poor grain yield is expected. Soybean stubble can be also be harvested as hay after grain harvest, however its forage quality will be marginal.
Although not as common in the eastern half of the state, grain sorghum is also utilized for a potential doublecrop option after wheat. Grain sorghum seed is generally less expensive than soybean seed. However, grain sorghum usually requires more fertilizer expense, primarily nitrogen. Weed control can be an issue with sorghum, although herbicide expense is increasing in other crops because of the increase in herbicide-resistant weeds in other crops and new herbicide options are becoming available in grain sorghum. Under favorable conditions, doublecrop grain sorghum can be a very profitable grain crop. However, if drought and heat occur during the mid to late summer and grain yield potential looks very low, sorghum can still be used as a quality forage crop.
Sorghum has some nice advantages as a forage crop. Sorghum can produce good biomass and retain its leaves well into the fall and winter. And because it acts like a perennial plant, it will keep producing new biomass until the first killing frost in the fall, even after a grain harvest.
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