June rains have significantly improved planting conditions for growers in the Upper Southeast, but are hampering efforts to quickly harvest one of the largest wheat crops in recent years in the Carolinas and Virginia.
North Carolina State University Small Grains Specialist Randy Weisz says, “Wheat grain moisture levels around the state are being reported in the 16 to 22 percent range. While we usually wait until wheat is closer to 15 percent to harvest, the prolonged exposure to high humidity and rain, combined with lodging, is resulting in grain sprouting in the head.”
The wet weather conditions have left wheat growers between the proverbial rock and hard place. Prolonged dry weather could substantially improve wheat quality, but leaving it in the field is more than a weather risk.
Weisz says, if growers have the capacity to dry grain they need to be getting this crop out of the field.
University of Kentucky researchers recently released a publication on managing high moisture wheat, which Weisz says could be very helpful to many growers in the Upper Southeast who have little experience growing wheat over the past few years, and for some who have never grown the crop.
The publication, “Harvesting, Drying and Storing Wheat” is written by University of Kentucky researchers Sam McNeil, Doug Overhults and Mike Montross. It can be obtained from the University of Kentucky’s College of Agriculture or accessed online at http://www.uky.edu/Ag/GrainCrops/ID125Section10.html.
Many growers in the Upper Southeast are ready to harvest wheat now, but much of the crop isn’t at the 13-15 percent desired moisture level, and some fields aren’t even close to the optimum drying level.
The time to start harvesting high moisture wheat, according to the Kentucky report is: As soon as the crop has field dried enough that it can be handled safely.
Hand-held moisture meter is ideal
A hand-held moisture meter is ideal to determine crop moisture, but if one is not available growers can weigh a half pound or so of seed and cook on a cookie sheet at 260 degrees F for 10 hours or so.
Then re-weigh the seed and calculate the moisture content by using this formula: (wet weight – dry weight)/wet weight × 100 = seed moisture (percent) For example, if a 0.5 lb sample weighs 0.4 pound after drying, seed moisture is 20 percent (0.5 – 0.4)/0.5 × 100 = 20 percent).
Most wheat growers with limited experience growing the crop are more familiar with corn and corn dryers can be used to dry wheat.
Any wheat harvested at higher than 17 percent moisture should be dried to 14 percent or less within 48 hours after harvest to prevent sprouting and spoilage.
When using corn dryers, growers are reminded that corn contains more moisture than wheat. For commercial wheat, drying temperatures should be below 140 degrees F and for seed wheat below 110 degrees F.
Corn bin dryers can easily be adapted to dry wheat, but growers are urged to make necessary adjustments when doing so.
The University of Kentucky researchers say, “Bin drying methods are easily adapted for wheat if adjustments are made to compensate for the increased resistance to air flow (measured as static pressure in inches of water).”
A rule of thumb, they say, is to limit wheat depth to half that used for corn. Centrifugal fans may be used to deliver higher airflow rates under higher static pressures. However, for a 30-foot bin, wheat depths greater than 20 feet will generally reduce airflow rates to less than 1 cubic foot per minute for each bushel (cfm/bu) in the bin, even with up to three 15-hp fans.
“Some in-bin corn drying systems are operated by filling the bin completely full within 2-5 days.
“Under no circumstances should you attempt to follow this practice in drying high-moisture wheat,” the University of Kentucky researchers say.
Weisz points out that over-drying wheat should also be avoided to maintain quality and best marketability of the crop. Drying wheat grain below the base market level of 13.5 percent wet basis should be avoided to maintain highest quality standard, if the crop is sold at harvest, he says.
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