You Need to Build a Strategy to Manage Kochia in Your Fields

You Need to Build a Strategy to Manage Kochia in Your Fields

Holly Thrasher

Dec 05, 2019

Often referred to as tumbleweed, kochia is a plant native to central and eastern parts of Europe and Asia. Kochia has historically been used for hay and silage, helping U.S. livestock producers survive the droughts of the 1930s and 1950s.

While kochia isn’t known for having good forage quality, when plants are young they are easily consumed by all classes of livestock. It also provides valuable cover and food for upland game birds, deer and pronghorn. 

Today, however, kochia is thought of as an invasive species.

Kochia is well adapted to the hot, dry conditions of the Great Plains and western regions of the U.S. and Canada. But like many weeds, it can rob moisture and valuable nutrients away from your crops. Since it tends to grow in areas of the West where moisture is already limited, this can be especially concerning. Early-emerging kochia can reduce crop yields by up to 70 percent.2

What is most concerning is that it has been found to have resistance to herbicides in several groups, including:

  • Group 2 - ALS inhibitors

  • Group 4 - Synthetic auxins

  • Group 5 - Photosystem II inhibitors

  • Group 9 - EPSP synthase inhibitors

Why we see resistance in kochia

Much like in our previous discussions about resistance in Palmer amaranth and waterhemp, kochia is able to develop resistance rapidly due to high genetic diversity, short seed life and heavy reliance on herbicides for control.

Each growing season, a single kochia plant can produce up to 30,000 seeds, and mature seeds can germinate immediately if conditions are optimal. In fact, kochia can begin germination as soon as the top 1-1.5 inches of topsoil are frost-free and temperatures reach 50 degrees Fahrenheit.1 Kochia seed can germinate in 2-3 hours under favorable conditions.2 Multiple flushes of weeds can occur throughout the growing season, sometimes from March all the way to late August or early September. 

One thing that makes kochia unique is the way it disperses its seeds. When the mature plant breaks off at the base, it becomes a tumbleweed and spreads its seeds as it rolls by.  

How to manage kochia

Crop rotation is key for controlling kochia and limiting resistance issues. Rotating crops is also beneficial because there are more effective herbicide control options for grass crops than broadleaf, especially post-emergence.

It is important to control kochia at or before planting because of its fast moving emergence patterns and dense populations. There are few effective post-emergence options for kochia in broadleaf crops. 

Planting cover crops and utilizing tillage practices can be an effective line of defense against kochia populations.

Using a soil-applied/pre-emerge herbicide with residual activity is going to be critical in your herbicide program—catching this difficult-to-control weed before it germinates or while it is still small will increase your odds of control.

Here are some herbicide options for controlling kochia in both soil-applied/pre-emerge and post-emerge scenarios.

Soil-applied herbicide options2:
Post-emergence herbicide options2:

Spray coverage and volume, adequate herbicide rates, proper adjuvant selection and tank mix partners are all critical factors in getting successful weed control and preventing further resistance to MOAs. Remember that use of single MOA herbicides is what helped create the challenges we now face in getting effective weed control. Always read and follow the label directions.

Looking for herbicides to control kochia and other weeds?

You can build a solid management strategy and save money when you buy ag chemicals through FBN Direct℠. As a member of the FBN℠ network, you can unlock low prices on hundreds of quality products to help your operation maximize its profit potential.


Sources:

Additional Sources:

https://ipmsymposium.org/2015/Documents/Presentations/11-1_Stahlman.pdf

https://extension.colostate.edu/topic-areas/natural-resources/identification-and-management-of-kochia-and-russian-thistle-6-314/

Stubbendieck, James L (2003) Weeds of the Great Plains. Lincoln, Nebraska (University of Nebraska-Lincoln); p 259

ALWAYS READ AND FOLLOW LABEL USE INSTRUCTIONS. It is a violation of federal and state/provincial law to use any pesticide product other than in accordance with its label. The distribution, sale and use of an unregistered pesticide is a violation of federal and/or state law and is strictly prohibited. It is your responsibility to confirm prior to purchase and use that a product is labeled for your specific purposes, including, but not limited to, your target crop or pest and its compatibility with other products in a tank mix. This information should not be used as a replacement for consulting the applicable product label. Consult the label for the most complete and up-to-date information about any referenced product. Readers must have a valid applicator license to use restricted use pesticides. Please consult your state department of agriculture for complete rules and regulations on the use of restricted use pesticides, as some products require specific record-keeping requirements.Scoparia Herbicide, Balance® Flexx, Huskie® Herbicide and Laudis® Herbicide are registered trademarks of Bayer CropScience. Spartan® 4F and Authority® XL Herbicide are registered trademarks of FMC Corporation. Sharpen® powered by Kixor® herbicide, Zidua® Herbicide and Armezon® herbicide are registered trademarks of BASF Ag Products. Valor® SX Herbicide and Cobra® Herbicide are registered trademarks of Valent U.S.A. LLC Agricultural Products. Callisto® is a registered trademark of Syngenta Crop Protection, LLC. Starane® is a registered trademark of Dow AgroSciences LLC."Kochia scoparia" by Matt Lavin is licensed under CC BY-SA 2.0

Holly Thrasher

Dec 05, 2019