The latest edition of Chemical Weed Control for Field Crops, Pastures, Rangeland, and Noncropland is now available at county Extension offices and online at: http://www.ksre.ksu.edu/bookstore/pubs/SRP1099.pdf
Much has changed in the magnitude of the weed control guide over the years, but the purpose remains the same.
In 1967 it consisted of 12 pages, with large print and a lot of white space. The current guide is about 135 pages with very condensed print and contains much more herbicide information. It has always been intended to be a resource to help farmers and crop advisors with selecting herbicides and using them appropriately.
The 1967 edition listed 16 herbicide active ingredients while the latest edition includes 93 active ingredients. In addition to those 93, the guide also includes generic products and pre-mix combinations.
Probably the first place you would go to for reference would be the efficacy tables. They have the various herbicide treatments and combinations listed by application timing, whether that is a preplant, preemergence, or postemergence herbicide. Then it provides ratings for the kind of weed control we would anticipate on the common weed species in those crops.
We base the information included in the guide on field trial evaluations done by K-State scientists, evaluations of new and established herbicides for crop tolerance and weed control, and recommendations from chemical professionals and other agronomists who have performed herbicide testing in other states.
Along with the efficacy tables is information about safe use and handling, protective equipment and herbicide resistance management. There is also a cost table available, which is developed by soliciting information from distributors and adding in a percentage markup for retail. It does not account for discounts that might be available through local retailers, so growers might end up paying less than the amount projected.
Additionally, there is information about managing pastures and rangeland, land enrolled in the Conservation Reserve Program, noncropland and noxious weeds as well.
The guide is just one source for weed control. People should also consult their local crop advisors on herbicide application, as products might perform differently in certain parts of Kansas. It is also not meant to serve as a replacement to the herbicide label, which is important for people to read.
The herbicide label is the law, and that’s the resource you should go to when using those herbicides. But, this guide does provide some comparisons, restrictions and how the various herbicides should be utilized.
It is surprising how many changes have to be made to the guide annually. Therefore, anyone who has an outdated copy should get the 2014 edition.
Dallas Peterson, Weed Management Specialist
(Based on a news release by Katie Allen, K-State Research and Extension News.)