Weather helps crops continue to thrive

Clean fields mean higher yields.

Monday's U.S. Department of Agriculture crops and weather report said temperatures last week were slightly below normal, which helped crops and livestock. Many farmers were finally able to finish herbicide applications.

Flowering can start anytime for soybeans. Plants will soon be dividing their energies between reproduction and additional vegetative growth. Crop experts said weedy fields will make this process more difficult.

"Research has shown early season weed competition reduces soybean yields," said George Cummins, Iowa State University Extension crop specialist based in Charles City, in Crop Notes, a periodic crop newsletter to ag professionals.

ISU and many crop professionals recommend that a pre-plant or pre-emergence herbicide be used to compliment a glyphosate program.

The report said soybean emergence is slightly ahead of last year at 97 percent, but behind the five-year average. The crop is rated 1 percent very poor, 3 percent poor, 16 percent fair, 59 percent good and 21 percent excellent.

Yield-robbing soybean aphids aren't a problem yet in Iowa, according to ISU crop specialist Brian Lang. Sunday's count at the Decorah research plot was 68 percent of the plants averaging three aphids per plant.

"The hot weather two weeks ago increased beneficial insect presence and has held aphid development in check. However, with continued normal temperatures and below normal rainfall I expect aphid development to start increasing again," Lang said in Crop Notes.
Aphid activity is actually running a little higher in central and northwest Iowa than it is in Northeast Iowa, he said.

The corn crop has just begun to tassel in some parts of the state. Two-percent is tasseled compared to the five-year average of 11 percent.

According to the report, the state's corn is rated 1 percent very poor, 3 percent poor, 14 percent fair, 55 percent good and 27 percent excellent.

"With everything planted and most weed control finished, we'll hope timely rains and few pests will allow the crop to continue development without interruption," said Bill Northey, Iowa secretary of agriculture and land stewardship, in a statement.

Some wind damage was recently reported in oat fields top heavy with grain nearing harvest. Thirty-two percent of the crop is turning color, and 96 percent is rated in fair or better condition.