Wisconsin Crop Manager newsletter

Author:	WCM Staff	Created:	4/21/2006 11:13 AM
Weed woes

Weed Quiz: Weeds in Corn

By WCM Staff on 5/29/2008 8:56 AM

What is the best timing to control weeds with a herbicide in corn? Does your answer change if question #1 is changed to “What is the best timing to manage weeds in corn?”

Successful preemergence corn herbicide programs require two key components. First, the programs need dry weather (with limited wind) in order to have the preemergence herbicides applied. Second, the programs generally need 0.5 to 1 inch of rainfall to activate the herbicide after the application, which moves the herbicide from the soil surface into the zone where weeds are germinating.

Cleaning Herbicides from Sprayers

By WCM Staff on 5/21/2008 2:53 PM

The potential for crop injury from herbicide contaminated sprayers is generally greatest with postemergence applications. Without proper clean out of sprayers, herbicide residues from one spray load can contaminate the next load and injury a sensitive crop. This is logical because the spray is making direct contact with the crops and is not being diluted with soil as with preemergence applications. Also, postemergence herbicides obviously have foliar activity, which may not be the case with all of the preemergence herbicides.

Herbicides Kill Weeds – Why not the Crop?

By WCM Staff on 5/15/2008 1:25 PM

Why is it that crops are not harmed by herbicides? The simple explanation is that some plants are able to metabolize (or detoxify) the herbicide into non-toxic chemicals before they damage the plant. However, before the discussion continues about metabolism, a quick review about herbicide mode of action is justified.

Managing invasive plants in fields enrolled in the CRP in Wisconsin

By WCM Staff on 5/8/2008 4:46 PM

Due to the uniqueness in managing CRP fields, we have developed specific factsheets to help in developing management plans for these listed species in CRP fields (see links).

Brush management guide updated

By WCM Staff on 5/7/2008 10:47 AM

Within this guide is an overview of the various methods of management available for woody species including cultural, mechanical, and herbicidal techniques. In addition, this document summarizes information on the effectiveness of application methods with specific herbicides on common brush species of Wisconsin.

No-See’m Weeds

By WCM Staff on 5/1/2008 3:25 PM

Despite the recent snow for some, cold weather, and wet fields, weeds are still germinating and emerging. However, pressure may mount to plant corn or soybeans without controlling these weeds first.

Don’t Fertilize Your Weeds

By WCM Staff on 4/23/2008 3:38 PM

Considering the cost of nitrogen, we can ill afford to allow weeds to use this expensive input. We conducted an experiment for the past 2 years that provided results that truly surprised us in regard to weeds and nitrogen. Basically, we confirmed that weeds are highly effective consumers of nitrogen.

Cadet and Authority Assist Herbicides

By WCM Staff on 4/23/2008 3:36 PM

Cadet is a new postemergence broadleaf herbicide for use in corn and soybeans from FMC. Authority Assist is a premix for preemergence broadleaf weed control in soybean.

Callisto Labeled on Oats

By WCM Staff on 4/23/2008 3:35 PM

A supplemental label for Callisto has been posted on CDMS that allows preemergence or postemergence applications for broadleaf weed control in oats.

Herbicide + Nitrogen Applications to Winter Wheat

By WCM Staff on 4/17/2008 2:24 PM

A question was recently asked about restrictions of applying herbicides using nitrogen fertilizer as the carrier. Obviously, a simultaneous application can save the time and expense of separate applications. However, it would be a poor choice if there is a risk of causing crop injury, especially considering the value of the current wheat crop. Summary comments on this issue are provided in this article.