Any of the above grades is classified as infested if more than two stored-grain pests are found in a 1000g sample. 0.2 percent 5 percent 3 percent U.S. No. Table 4 . Seal all unnecessary openings before loading the bin, and seal the aeration fan, top vents, eaves, and anywhere else you can see light coming through the bin. Poorly sealed bins are the number-one cause fo fumigation failures.
Many fumigation attempts end in failure.
Be sure to leave the fumigant in the bin long enough to be effective. Read the fumigant label to determine how long it will take the fumigant to reach a lethal level. To increase fumigant efficiency, place two-thirds of the fumigant pellets in the top 6 inches of grain, and place the other third in a metal or cardboard tray in the aeration duct. In large bins, it may be necessary to probe some fumigant as deep as possible into the grain mass. If the bin is only partially filled, probe fumigant pellets into the grain, and then place a tarp over the grain to keep the fumigant in the area with the grain.