If you found kochia in this year’s cereal crops, there’s no doubt this troublesome weed will be present next year as well. Now is the time to plan your kochia control strategy for the 2024 growing season.
Fast Facts on Kochia
- Kochia is both drought-resistant and cold-hardy. This weed is capable of producing forage with as little as 6 inches of annual rainfall.
- Mature kochia plants grow up to 7 feet tall, with an extensive root system that can extend 15 feet into the soil and 21 feet in diameter.1
- Adult kochia plants can produce up to 30,000 seeds.1
- The weed seeds spread via a “tumbleweed” mechanism, meaning a mature stem will detach from its base and then be blown around by the wind.
- Seeds do not remain viable in the soil for an extended period, but they exhibit a high initial germination rate. Under favorable conditions, seeds initiate germination within two to three hours and seedlings establish quickly.1
- Kochia has an imperfect flower that allows cross-pollination, increasing the potential of herbicide resistance.
- Populations of kochia resistant to atrazine (photosystem II inhibitor) were first reported in 1976. Kochia resistance to sulfonylurea herbicides (ALS inhibitors) was first reported in 1987 and is now considered widespread.
- Kochia populations resistant to glyphosate were first reported in 2007 in Kansas. Since 2007, glyphosate-resistant kochia has spread throughout the Great Plains and western United States.
Controlling kochia at an early stage is vital to prevent yield loss. If kochia is a challenge, you may consider implementing the following practices on your cereal operation:
- Early tillage in the spring provides good control of kochia during its early seedling stage.
- Crop rotation (where practical) has proven effective for managing kochia.
- The use of multiple herbicide modes of action and diverse application timing is recommended to control numerous flushes of the weed throughout the season. This may include burndown, preplant, pre- and postemergence, and postharvest applications.
- Rezuvant® with Arylex® active, PerfectMatch®, Pixxaro® EC with Arylex® active and OpenSky® herbicides from Corteva Agriscience offer effective control of kochia.
- New Tolvera™ herbicide will deliver a non-Group 4 herbicide for kochia control with the ability to tank-mix with groups 1 and 2 herbicides. Tolvera is expected to obtain registration with the U.S. Environmental Protection Agency in time for the 2024 growing season.
Note that each operation is unique, so effective control measures will vary. Consult your local retailer or Corteva Agriscience representative to determine the best weed control strategy for your operation.
1United Soybean Board. 2023. Kochia. https://iwilltakeaction.com/weed/kochia
OpenSky®, PerfectMatch®, Pixxaro® EC and Rezuvant® are not registered for sale or use in all states. Contact your pesticide regulatory agency to determine if a product is registered for sale or use in your state. Tolvera™ has not yet received regulatory approvals, approvals are pending. The information presented here is not an offer for sale. Arylex® is a registered active ingredient. Always read and follow label directions.