At the start of the summer, the aphid was restricted in its distribution to SE Minnesota. To reach this area in one growing season, it is estimated the aphid spread at an average rate of 3.1-6.3 miles per day. This rate was not constant throughout the season; from 12-26 June, the area affected by soybean aphid increased at a slow to moderate rate (from 0 to 5 miles per day), from 27 June - 3 July, spread was rapid (approximately 8 miles per day), from 4 - 31 July, spread was slow to moderate (0 to 4 miles per day), from 1 – 7 August, the rate of spread increased to slightly more than 6 miles per day, and through the remainder of the growing season, aphid spread continued at a moderate to slow pace.
It is still unknown if this insect will become a permanent pest of soybeans in NW Minnesota. It appears that the most serious yield loss occurs from aphid populations developing early in the season. If soybean aphid cannot overwinter in NW Minnesota, it still may become a weather-mediated pest, being blown into the area on weather fronts and becoming established in the crop late in the season. If this is the case, the yield loss due to aphid infestations may be considerably lower in this region than in the southern part of the state. It is still unknown if soybean aphid can overwinter in this region.
The map below shows the distribution of soybean aphid in Minnesota at the end of the 2001 growing season.
For more information, check out the Minnesota Soybean Aphid webpage on MN Soybean Producer's Just For Growers website.
Grasshoppers -
Minnesota Grasshopper Management - 2000 with
color graphics
Minnesota Grasshopper Management Brochure with
scouting and control information (available as a PDF file designed to be as a
tri-fold brochure).
Scouting -
Scouting for Insects in Wheat, Alfalfa, and Soybeans
- a manual prepared for the University of Minnesota Extension Service Field
School, held at the Northwest Experiment Station, Crookston, MN, July 7-8,
1998.