Volume
6 Issue
11
August 11, 2009
Mid-August
Means Soybean Aphid Decisions
Field situations are changing quickly with regard to soybean aphid
populations. In NW MN aphid numbers are increasing, but in many
areas the differences between nearby fields can be quite
significant.
Soybean Growth Stages for Pest Management Decisions
Management
decisions on whether to treat soybean aphids will be affected by the
soybean growth stage in a field during the next two weeks. As plants
progress to the later reproductive stages (e.g., R5, R6, R7, etc.)
risk of yield loss from aphids declines. Here is
a summary of how to recognize growth stages in the field.
“Speed Scouting” Exercise on the Web
Iowa State University entomologists have posted an exercise that
helps to illustrate the soybean aphid speed scouting process. This
method can get you in and out of fields with effici3ent use of your
time AND help make a reliable treatment decision on your fields. So,
if you still don’t like counting aphids and the recent reports have
you wondering about what is happening in your fields, try the
exercise and see just how simple it can be.
Late-Season
Glyphosate Applications in Roundup Ready Sugarbeet
Glyphosate can be applied to Roundup Ready sugarbeet up to 30 days
prior to harvest. Therefore, glyphosate should not be applied in
any fields that will be harvested in the first two weeks of
pre-pile. There is certainly still time to apply glyphosate to
sugarbeets that will not be harvested until October.
Hand-weeding – Why is it Important?
As I drive around Minnesota and North Dakota, I see weeds emerging
above crop canopies. If these weeds are due to herbicide
resistance, then the best management strategy is to remove the
plants by hand, unless the weeds are too frequent. A plant that
survives an herbicide application, but is removed prior to seed
production, can not add to the frequency of resistance within the
field.
Comments to
Consider on Foliar Feeding
Soil scientists and agronomists agree that nutrients essential for
growth and development enter the plant either through leaf tissue or
roots with uptake by roots clearly dominating the absorption
process. For many years, however, the concept of absorption by leaf
tissue has intrigued many researchers.
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