To excel as a crop scout in soybeans, the best tool of the trade is a sweep net. I find the sweep net a perfect tool for first detection of insects in soybeans--or alfalfa. In a few, quick minutes, a field can be swept and the contents examined. If the insect in question is found, say bean leaf beetles, then a more thorough process can be implemented to determine the number of insects per plant, length of row, etc. A sweep net is helpful for scouting bean leaf beetles and caterpillars in soybeans, and is absolutely essential for scouting potato leafhoppers in alfalfa. Sometimes it can be used to make the first detections of soybean aphids as small populations can be hard to find when searching for them visually.
The net I use is a hybrid net whose components are made by two different supply houses. I recommend buying the handle from Ward's because of its 3-foot-long, strong metal construction and heavy wire gauge hoop, but their net bag is of poor quality. I recommend replacing the Ward's net bag with one made by BioQuip. The bag from BioQuip is extremely durable--the edge is made of Dacron sail tape--and slides easily through soybeans during sweeping. The Dacron is extremely resistant to abrasion and should last throughout the growing season, plus it will not roll up on the leading edge of the net hoop like the more flimsy net bag from Ward's. Unfortunately, the BioQuip net handle is wood and a short 2 feet long. For these reasons, I suggest buying the parts and making a hybrid sweep net.
The hybrid sweep net is not inexpensive, but it will serve you well in collecting insects in soybeans or alfalfa. I strongly encourage you to get one if you'll be scouting either of these crops this season.
Here are the components for my hybrid net:
Heavy-duty beating net #10V0560
(Net has 36" aluminum handle with plastic grip and frame of steel)
Ward's Natural Science Establishment, Inc. P.O. Box 92912 Rochester, NY 14692 1-800-962-2660
15" heavy-duty beating net replacement bag
#7215HS (Made of rugged sailcloth banded at top with Dacron sail tape)
BioQuip Products, Inc. 2321 Gladwick St. Rancho Dominguez, CA 90220 310-667-8800
Marlin E. Rice is a professor of entomology with extension and research responsibilities in field and forage crops.
This article originally appeared on page 81 of the IC-498 (3) -- March 26, 2007 issue.