Cropping Issues in Northwest Minnesota

Survey results from July 5 through 19. Similar to the regional scouting results from June 28 through July 12, the scouts tasked with carrying out the soybean aphid survey described last week in northwest and west-central Minnesota found no aphids through last week Friday, July 19 (Figure 1).

Soybean aphids spend their winter as eggs on buckthorn plants. After emerging from their eggs aphids spend a bit of time on buckthorn. Winged soybean aphids then soon find their way into adjacent soybean fields. Earlier planted soybean fields and the edges of fields nearest wooded areas inhabited by buckthorn are likely locations each year to first find soybean aphids.

Topics and speakers for next week's Crops & Soils Day at the Northwest Research and Outreach Center (NWROC) have been finalized (Figure). Join University of Minnesota staff on Wednesday, July 17 at the NWROC's North Farm, located one mile north of the University of Minnesota Crookston campus on Hwy 75 N (GPS: 47.81853, -96.61326). Registration for the morning small grains tours begins at 7:45 AM and wagons leave at 8:15 AM. While there are two morning tours, people can attend each of the nine morning presentations as the wagons will travel back to the registration area for a short break before switching routes.

The following article was written on July 8 (before storms rolled through much of NW MN) by UMN Extension small grains agronomist Dr. Jochum Wiersma.  The risk assessment models for FHB continues to show a near continuous high risk for FHB in all of Minnesota but the northern half of Polk County and the counties of Marshall and Kittson and the eastern beach ridge of the Red River Valley between Thief River Falls and Fergus Falls.  Like last week's update - much of the difference in risk can be explained by overall drier conditions in those areas. 

The pinkish-white fungus that causes Fusaium head blight (FHB) can sometimes be observed in humid conditions. The following article was written on July 3 by the UMN Extension small grains agronomist Dr. Jochum Wiersma.

The article and video were originally posted by UMN Extension soil scientist Dr. Daniel Kaiser. Micronutrients are “small but mighty” elements required by plants to complete their life cycles. Plants take up less than one pound of micronutrients per acre, with only a few ounces required for optimal crop production. While micronutrients are needed for optimal plant growth, they may not need to be applied.

This article was written by UMN Extension IPM specialist Bruce Potter and entomologist Bob Koch.   A video of soybean gall midge larvae on soybean was captured by Bruce Potter and can be found here .  Adult soybean gall midge (photo: N. Staves, UMN IPM). As part of a multi-state project funded by the soybean checkoff, three adult soybean gall midges were captured between June 17 and June 20 in emergence cages placed in a field in Rock County, MN. Another adult was captured in that field between June 20 and June 24. This was one of three Rock Co. fields, infested with soybean gall midge during 2018, where we are currently tracking emergence of this pest. The other cages located in this county and elsewhere in Minnesota (Olmsted, Stearns, Ottertail, Wadena counties) have not yet detected adults. Compared to some of the fields in nearby states that were heavily infested in 2018, these Minnesota captures are low. However, not all heavily infested fields located outside M...