Is glyphosate less effective than 10 years ago?

Can you recognize the presence of glyphosate-resistant weeds in a field?

by Phillip Glogoza, Extension Educator, Crops

Management decisions on whether to treat soybean aphids will be affected by the soybean growth stage in a field during the next two weeks. As plants progress to the later reproductive stages (e.g., R5, R6, R7, etc.) risk of yield loss from aphids declines. Currently, the soybean crop ranges from R3 to R5. Insecticide treatments for R5 stage soybeans may respond positively to soybean aphid treatments when populations exceed threshold, however the level of the yield response is less predictable. Early R5 treatments are more likely to realize a positive response than late R5 treatments. Treatments for aphids are generally not recommended beyond the R6 growth stage.

by Dr. Ian MacRae, U of MN Extension Entomologist

There has been increasing pressure to apply insecticide and tank mixed pesticides at lower thresholds based on claims of increased yield benefits. While increased commodity prices can stimulate the desire to decrease risk tolerance and increase the use of pesticides, this is not always a paying proposition.

by Dr. Ian MacRae, U of MN Extension Entomologist

.... Low populations of Soybean Aphid (SBA) have been reported throughout NW MN and NE ND. Populations are still low and generally not on more than 30% of the plants. The cooler weather will slow reproduction for a few days but it is predicted to warm up by the weekend, at which time we'll start to see some more population growth and dispersal across fields. Although most fields are well below treatment levels so far, it is time to start scouting the soybean fields, getting a handle on what populations you may have and tracking progress and population growth.

by Dr. Charla Hollingsworth, U of MN Extension Plant Pathologist

In 1954, the first detection of the soybean cyst nematode (SCN) occurred in North Carolina. Since that time, the nematode has become the most important disease issue of soybean in the world. Spread with soil, this microscopic roundworm continues to gain ground in Minnesota soybean-producing areas. Essentially anything that can move small particles of soil will also transport this nematode.

by Phillip Glogoza, Extension Educator - Crops

A lot of wheat is now heading in NW Minnesota. In the northern most counties, degree day accumulations are just reaching the 1300 DD mark (see map), the point where 10% of female midge have emerged. Emergence will continue through 1600+ DD (90% female emergence).