The dry conditions that have prevailed over much of Kansas since the fall of 2017 have left some wheat growers with relatively dim prospects for grain production for the summer 2018 harvest. An alternative use for that wheat is as a forage crop — silage or hay — which may still have considerable value at a time when pasture grazing prospects and hay supplies may be uncertain. This article briefly looks at some issues producers should consider as they contemplate their options for their drought-stressed wheat.
Wheat silage and hay can be valuable feedstuffs for cattle producers. Wheat harvested at the dough stage should contain approximately 56 to 62 percent total digestible nutrients and 8 to 11 percent crude protein, on a dry matter basis. Wheat silage and hay may be used in the diets of feeder cattle, calves, replacement heifers, and beef cows. However, if the wheat is harvested post-heading, producers should grind the wheat hay if the variety has awns, since awns can cause health problems if fed unground.
Producers looking at these alternative uses for their wheat crops should also consider their options for marketing each type of feedstuff. For those who do not have their own cattle to feed, prospective demand for either silage or hay from nearby livestock producers could play an important role in their decision. Hay is more flexible in that it can be hauled farther and may be of use to a wider potential clientele.
Finally, insured wheat growers should check first with their crop insurance agent regarding insurance requirements to document potential grain yield losses before harvesting a forage crop. If producers believe they would have low grain yields and otherwise be entitled to an insurance indemnity, they may be required to leave small areas of uncut wheat to provide a way to estimate grain yields for the insurance loss calculation. Insurance agents can also inform producers of any other restrictions which may apply.
Making wheat silage
Timing is a key factor for making small grain silage. Small grain forage yields and feeding values depend heavily on the stage of maturity at the time of harvest. The optimal moisture level for ensiling small grains is 62 to 68 percent. Moisture levels above 70 to 75 percent can cause excessive seepage and undesirable fermentation. At lower moisture levels, the silage may contain more hollow stems and result in excessive air entrapment. This possibility means that small grain silage should be chopped finer than corn or sorghum silage. Timing is crucial in obtaining these target moisture levels. It is often more of a challenge to put up small-grain silage with adequate moisture if harvesting at soft-dough, which requires little drying time between swathing and chopping, while putting up silage in the boot stage may require some drying time between swathing and chopping. Carefully monitor moisture content when swathing and chopping. Wheat maturity can advance quickly, so producers with significant acreage to harvest may consider whether to begin while the grain is still in the milk stage, when moisture content is typically 65 to 70 percent.
Information from New Mexico State University Extension indicates there are actually two schools of thought on the timing of small grain silage harvest. The more conventional perspective aims for ensiling during the late-boot/early heading period because energy and protein are optimized. The quality may be high enough to use for lactating dairy cows. The second perspective argues for waiting until the soft-dough stage; while this later harvest results in lower energy and protein per ton, the increase in yield is usually enough to offset the decline in quality. That is, more protein and energy will be harvested on a per acre basis.
Under typical growing conditions, wheat silage yields will be in the range of 5 to 7 tons per acre of 35 percent DM forage when harvested in the late boot stage, and 8 to 10 tons per acre in the late-dough stage. Of course, drought-stressed wheat will likely produce less tonnage per acre; depending on the severity of drought, a 25 to 50 percent reduction in biomass can be expected.
Stacy Campbell is a Kansas State Research and Extension agent in Hays for the Cottonwood Extension District Office.