NEWS RELEASE ISSUED BY THE UNIVERSITY OF MISSOURI EXTENSION OFFICE
Wind is an Important Factor When Applying Herbicides
LAMAR, Mo. -- Jill Scheidt, agronomy specialist with University of Missouri Extension in Barton County, scouted fields west of Lockwood on June 18 for the crop scouting program.
Corn is in the 14-16 leaf stage. “The corn should tassel within the next two weeks. A minor amount of rust was seen on some varieties, but nothing to worry about; rust rarely requires treatment in Missouri corn,” said Scheidt.
Scheidt identified Paraquat herbicide injury on corn in at least one field. Paraquat is a highly volatile herbicide used in soybeans that can drift more than one mile from the location where it was applied.
“If there is wind, wait to apply Paraquat to prevent injury to non-target plants, even if using a drift retardant,” said Scheidt.
She found soybeans in the 4-5 trifoliate stage. A little herbicide burn from Prefix was seen, the new leaves are unaffected so the plants will recover. She also found some insect feeding.
“Soybeans can tolerate up to 30 percent defoliation before bloom before treatment is required,” said Scheidt.
In the wheat fields, she found wheat in the hard dough stage. Harvest wheat at 13.5% moisture in order to prevent fungus development in the storage bin.
“If harvesting wet wheat, producers should dry wheat as it is going into the bin and make sure the first load is completely dry before adding more wheat. If the grain bin is filled all at once, the wheat at the top of the bin will not dry and may sprout due to humid conditions that occur in June and July,” said Scheidt.
Scheidt found Stagonospora blotch on some wheat heads. Wet weather conditions after flowering favor disease development in wheat.
“No fungicides are available for application at this time. Fungicides must be applied at the flag leaf stage if weather conditions are warm and humid to prevent stagonospora blotch,” said Scheidt.
The weekly field scouting report is sponsored by University of Missouri Extension and Barton County Extension. For more information on this scouting report, or to learn how to receive it a week earlier by telephone, contact the MU Extension Center in Barton County, (417) 682-3579.