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Wednesday, August 5, 2015

What to consider when treating a soybean field more than once for soybean aphid

by Robert Koch (Extension Entomologist), Bruce Potter (IPM Specialist), Ian MacRae (Extension Entomologist), and Ken Ostlie (Extension Entomologist)

Soybean aphid populations in many areas of Minnesota are increasing. This year, there are a number of factors making population development and management less predictable than in the previous couple of years:
  • Late summer dispersal of soybean aphids is currently occurring, bringing high numbers of winged aphids to colonize fields; sometimes those that were previously treated.
  • Forecasted weather conditions for the upcoming week look favorable for aphid population growth.
  • A number of fields in southwestern Minnesota have reported unexplained failure (poor performance) of recent insecticide treatments and will require additional applications to control existing populations.
All of these factors point to the importance of weekly scouting for soybean aphids and treating when populations reach the threshold of 250 aphids per plant when 80% of plants have aphids (U of MN guide to soybean aphid scouting). At the threshold, yield loss is not yet occurring, but will if aphids are not soon controlled.

If a field needs to be treated more than once in the same year, remember the potential for development of insecticide resistance (U of MN fact sheet on insecticide resistance). Do not reapply the same insecticide mode of action (insecticide group). For example, if a field was treated with an organophosphate insecticide and needs to be treated again for aphids or some other pest, such as spider mites, avoid using organophosphates for the second application. Instead, use a different insecticide group, such as a pyrethroid. The mode of action (or group) is on most insecticide labels.

Monday, August 3, 2015

Corn development and updated yield forecasts for the Corn Belt

Jeff Coulter, Extension Corn Specialist

Much of the corn in Minnesota has finished pollinating and kernels are in the blister to milk stage. Soil moisture levels and air temperatures for much of the corn in Minnesota were favorable during pollination and continue to remain favorable, but some regions are becoming dry.

Thursday, July 30, 2015

Hay Auction Summary July 2015 and Other Info

By Dan Martens, Extension Educator, Stearns-Benton-Morrison Counties,, 320-968-5077 if a local call to Foley or 1-800-964-4929

I am posting information and links to documents with data from:
July 2 2015 Sauk Centre Hay Auction and SEASON AVERAGES
And sources of other hay market information

1. July 2, 2015 Summary - All loads sold, grouped and averaged.

2. History of selected lots - Averaged for recent years, and each sale so far this year.

This include AVERAGES CALCULATED FOR THE 2014/2015 SEASON – listed on the first and third page.

3. Graph - Medium Square Groups from RFV 101-200, Grass Hay 5-9% Protein, Straw

The “heavy red line” is for the 2014-15 auction season. The vertical lines on the June 4 and July 2represents the range in price from high to low with a spot at the average.

4. Straw and Grass Graphs – Large Round Straw sold by the ton, Large Round Straw sold by the bale, Medium Square Straw sold by the bale, Large Round Grass 5-9% protein sold by the ton.

5. Dairy Tours & Field Days

Friday, July 24, 2015

Crop management field day to be held August 4 in Lewiston

A Crop Management Field Day is scheduled for Tuesday, August 4, from 9:00 a.m. to 12:00 p.m. in Lewiston, MN. Highlights include looking at split nitrogen application research plots in corn, hearing about new herbicide options and their effectiveness on problem weeds, and learning about cover crops. In addition, A new best management practice outreach program will be introduced by the Minnesota Department of Agriculture.

The event will be located in a field adjacent to the Lewiston Sales Barn at 21241 Dutchmans Crossing (Map). In the event of inclement weather, the event will be moved to the Green Lodge at Farmer's Park, located along MN-Hwy 14 between Lewiston and Stockton.

There is no charge to attend the field day. Pre-registration is preferred to help with refreshment and grounds planning: Call 507-457-6440 or visit to register.

For more information, see the Crop Management Field Day flyer.

Thursday, July 23, 2015

Tillage, Technology and Residue Field Day registration available online

Crop producers and other agricultural professionals can see the latest in variable depth tillage equipment, watch side–by–side field demonstrations by national and regional manufacturers, and learn how to build soil structure for maximum soil productivity at the field day scheduled for Thursday, September 10 from 9:00 a.m. to 3:30 p.m. The Tillage, Technology and Residue Field Day will be held at the West Central Research and Outreach Center (WCROC) in Morris, MN (Map). Other highlights for the field day include the following:

Wednesday, July 22, 2015

Topics Addressing Small Grain Crop Dry-down and Harvest

prepared by: Jochum Wiersma, Small Grains Specialist, 
                      Doug Holen, Crops Extension Educator and 
                      Phyllis Bongard, Educational Development and Communications Specialist

Small grain harvest is underway in parts of southern Minnesota including winter wheat, winter rye, barley, and even spring wheat.  The common theme to date is harvest maturity.  Many calls and questions are circulating addressing crop dry-down and removal.  Most of this concern comes on the back side of strong wind events across the state resulting in significant lodging. 

Monday, July 20, 2015

Parasitic wasps attacking Minnesota soybean aphids: Summary of a collaborative statewide survey

by Joe Kaser (Graduate Student), George Heimpel (Professor), and Robert Koch (Assistant Professor & Extension Entomologist)

An important group of beneficial insects that help control soybean aphids are tiny parasitic wasps (also known as aphid parasitoids). These wasps do not sting or harm humans, livestock, or any insects besides aphids. The biology of these parasitic wasps is like something out of a science-fiction movie. The female wasps inject their eggs into aphids. The larvae that hatch from the eggs then develop inside of their aphid hosts, eventually killing the aphid, and later emerging as winged adult wasps. Aphids attacked by these parasitic wasps become “mummies,” which are the slightly swollen, brown- or black-colored bodies of the dead aphids.  When managing soybean aphid, use of scouting and the economic threshold (250 aphids per plant) will help reduce insecticide inputs and conserve these aphid-killing wasps.  
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