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6. Scout Fields

bean leaf beetles

Accurate and timely scouting may prevent unnecessary pesticide treatments, and it helps you to identify potential problems before they become less manageable.

When scouting for insects, you typically need to look for both crop injury and the insects. However, scouting techniques will vary considerably, depending on the insect and crop involved. That's why it is important to obtain a field crop scouting manual.

counting plants In some cases, it will only be necessary to count the number of plants with or without injury. For many pests, the recommendation is to examine 100 plants—20 plants in five different parts of the field.
levels of soybean leaf defoliation In other cases, particularly in soybeans, you will also need to note the severity of the injury. In soybeans, this is most commonly done by determining the amount of defoliation.
Using a sweep net When looking for insects, you count them in a variety of ways: number of insects per sweep, number of insects per plant, number of insects per foot of crop row, and number of insects per foot or yard.
black nightshade As for weeds, scouting keeps you on top of shifting weed pressures and makes it easier to spot-treat for weed problems. Scout weeds 7 to 20 days after planting, then scout periodically for four to six weeks.
drawing a weed map In all sample areas, calculate the severity of the problem by counting the number of weeds per 10 feet of row for large infestations or every 100 feet of row for smaller infestations. Draw a weed map for each field early in the season and again just before harvest.
What to include in a weed map... The weed map should include notes on: specific weed species; the locations of perennial weeds; severe infestations of annual weeds; differences in weed populations in various areas of the field; weeds located in fence rows, near the edges of the field, and along waterways; and physical descriptions of the field itself.

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