As temperatures rise, pay attention to stored grain
Published on -3/30/2014, 3:49 PM
If you have grain bins and ever have put grain into storage at higher than recommended moisture content, you know that increases the likelihood of storage problems. Last fall, this might have occurred for some folks in the area. Most of the grain has been stored below 40 degrees thanks to our winter temperatures.
While that has kept mold and insect development at a standstill, warming temperatures could result in storage losses if not monitored. As average temperatures rise above 40 degrees, that means aeration will be necessary to manage moisture in the bin.
It's important you continue regularly to check grain thoroughly and take steps to maintain grain quality.
Ken Helleyang, Extension engineer at North Dakota State University, shares the following information on monitoring your stored grain. He describes how solar radiation can warm stored grain, creating an environment for grain storage problems. The daily total solar energy heating the south side of a grain bin Feb. 21 is more than twice the amount as June 21. Therefore, grain next to the bin wall might be warmer than the average outdoor air temperature.
Grain warming normally will be limited to a couple of feet near the bin wall and a few feet at the top of the bin. Monitor grain temperature, at least in these locations, to determine when to operate the aeration fan. Bin temperature cables help monitor grain temperature but only detect the temperature of the grain next to the cable. Grain has an insulation value of approximately R=1 per inch, so grain insulates the cable from hot spots just a few feet from the cable.
Do not operate the fan during rain, fog or snow to minimize blowing moisture into the bin. Bin vents can frost or ice over if fans are operated when the outdoor air temperature is near or below freezing, which might damage the bin roof. Open or unlatch the fill or access cover during fan operation to serve as a pressure relief valve. Cover the aeration fan when the fan is not operating to prevent pests and moisture from entering the bin and warm wind from heating the grain.
It is recommended to collect some grain samples and check the moisture content to assure it is at the desired level. However, many grain moisture meters are not accurate at grain temperatures below approximately 40 degrees. When the grain is cold, it should be placed in a sealed container, such as a plastic bag, and warmed to room temperature before checking the moisture content.
At temperatures above 40 degrees, the meter reading must be adjusted based on the grain temperature unless the meter measures the grain temperature and automatically adjusts the reading. Check the operator's manual for the meter to determine correct procedures to obtain an accurate value.
Natural air drying is not efficient until the average outdoor temperature reaches 40 degrees. The moisture-holding capacity, and therefore the drying capacity, of colder air are so limited that drying at colder temperatures is extremely slow and expensive. When natural air drying, adding supplemental heat primarily reduces the final moisture content of the grain and only slightly reduces drying time. Regardless, try to keep the temperature of the grain within 10 degrees of the average outside air temperature to limit condensation in the bin.
More information on grain storage management can be found at cropwatch.unl.edu/grainstorage2.
Stacy Campbell is
agriculture Extension agent in Ellis County.
Scout wheat for insects
There have been reports in northwest Kansas of sporadic army cutworm activity, brown wheat mites and winter grain mites. I have been out a few times in the last week and have not found any army cutworms, but did notice some brown wheat mites in a few fields. Army cutworms can be more of a problem with fields bordering grass or CRP. It is recommended you scout your wheat fields weekly for insect activity, and if you have any questions, contact your local K-State Research and Extension office.
Additional information on wheat insect management can be found at www.ellis.ksu.edu. Click on the Ellis County Agriculture page, and under Crop Links, click Facts & Information on Crop Pests.