Wisconsin Crop Manager newsletter

Author:	WCM Staff	Created:	4/21/2006 12:13 PM
Whats bugging you. Articles concerning insects on field crops in Wisconsin

Soybean Aphid update

By WCM Staff on 6/25/2008 2:32 PM

Soybean aphids made their debut in early vegetative soybeans in Wisconsin over the last two weeks. Reports in this article are from V2 to V4 soybeans. Populations are not of economic concern at this time. Weekly soybean aphid scouting should begin by late vegetative soybean growth stage and before early reproductive stage (beginning bloom). It is a good idea to monitor soybean fields for arrival of soybean aphid and colonization in your fields while checking soybean stands.

European Corn Borer update

By WCM Staff on 6/23/2008 2:54 PM

Degree Day accumulations suggest the southern ½ of Wisconsin is at, or just past peak European corn borer flight and the most opportune treatment timing (if needed) may be starting in southern Wisconsin. Spot-check earliest planted corn because it is more attractive to female first generation European corn borer moths to lay eggs.

What else is going on??

By WCM Staff on 6/19/2008 12:18 PM

There have been a few reports of armyworm damage on corn planted after a small grain cover crop or in dense weed growth. This is not out of the ordinary for this time of the year. But it does make you wonder what is happening in wheat. I’ve noticed some lodging of wheat from recent storms.

Alfalfa Weevil Development

By WCM Staff on 6/19/2008 12:15 PM

There has not been any widespread insect problems reported lately, but there have been some isolated reports of a few different problems. Alfalfa weevil is one that should be mentioned.

Seedcorn Maggot Injury to Soybean

By WCM Staff on 6/11/2008 1:31 PM

Shawn Conley and John Gaska, Dept of Agronomy, reported on the potential for reduced soybean seed quality this year and their concern for planting in cool wet soils. This article is just a quick reminder that seedcorn maggot may also be a contributing factor. Seedcorn maggot injury is often more severe during a cool/wet growing season and soybean are more susceptible to maggot injury than corn.

Diagnosing Early Season Corn Insect Damage

By WCM Staff on 6/11/2008 1:26 PM

It looks like we have finally turned the corner and are getting the warm weather we all hoped for. When the fields dry, a lot of us will be walking corn looking for early season problems. One thing is certain; you will find some insect injury.

Corn Rootworm Hatch Update for Wisconsin

By WCM Staff on 6/11/2008 1:18 PM

Figure 1, current through June 12th and forecasted through June 17th shows western corn rootworm egg hatch has begun in WI. During this period 1st-2nd instar rootworm larvae will be hatching in south central, southeastern, southwestern WI. East central and Northwestern WI larval hatch will follow suit.

Alfalfa Weevil in Second Crop Regrowth

By WCM Staff on 5/29/2008 10:54 AM

In the southern part of Wisconsin we have reached or exceeded 300 weevil degree days and damage reports have been on the quiet side. This could be a result of low weevil populations or a weather-friendly cutting schedule. If it was the latter, it might be worth some time to spot check fields for signs of damage to second crop regrowth.

Spot Check for Early Season Armyworm Damage

By WCM Staff on 5/28/2008 3:52 PM

Now isn’t the time we normally think about widespread armyworm damage in corn. However, it is the time when migrating moths are moving into the state and may cause damage to scattered seedling corn fields when/if field conditions are favorable. This spring migration is unpredictable in terms of incidence and severity.

Preparing for Stalk Borer Migration to Corn

By WCM Staff on 5/27/2008 2:01 PM

Degree day accumulations (base 41º) in southern Wisconsin indicates stalk borer eggs are hatching and migration to corn can be expected soon. Although there hasn’t been a lot of interest in their control recently, high corn/input prices may indicate a closer look this year.

New UWEX Pub – Western bean cutworm: A pest of field and sweet corn

By WCM Staff on 5/21/2008 5:15 PM

Western bean cutworm (WBC), traditionally a pest of the western Corn Belt, is an emerging pest in Wisconsin. As this pest will likely become established after arrival in a state, it is important that growers and agricultural professionals know how to identify and manage it.

Corn Rootworm Egg Hatch Update for Wisconsin

By WCM Staff on 5/21/2008 5:08 PM

With the relatively cool spring temperatures this year, insect development degree-days have been accumulating about 1-2 weeks slower than a typical spring. Corn planting is finishing up in Wisconsin, and growers and consultants will begin to ask about corn rootworm egg hatch and expected time frame of first through third larval instar corn rootworm feeding on corn roots.

Will we have Significant Alfalfa Weevil Damage in 2008?

By WCM Staff on 5/15/2008 12:41 PM

Last year we saw a noticeable increase in weevil incidence and severity compared to previous years. That by itself doesn’t mean weevil damage will be higher this year. But it does give us a reminder that we should continue to scout alfalfa fields in a timely manner.

Cool Wet Weather May Increase Secondary Insect Injury to Corn

By WCM Staff on 5/15/2008 12:38 PM

The cool, wet weather we’ve been experiencing has the potential to increase the amount of secondary insect injury to corn seed and/or emerging seedlings. The longer it takes corn to develop the longer it will be susceptible. The end results may be reduced stands and poor seedling vigor which are often mistakenly attributed to planter problems or poor seed quality.