Winning Solutions for Weed Control in Soybean Crops

April 12, 2023

Weeds are able to return year after year because of their life cycle and their methods of reproduction. This is why, to protect your soybean crop, it is important to have a good action strategy for every season!  Don’t know how to get started? Read on for our team’s top weed control tips!

Start early!

According to Guelph University researchers, a plant experiences physiological stress when surrounded by other plant species. It will quickly alter its behavior, which impacts its growth and its yield.

Soybean plants are very sensitive to the presence of weeds, especially up until stage V3. Weed control is therefore essential during this critical period to minimize losses.

Rotate your weed control products

A weed is said to be resistant when it survives and reproduces after a treatment was applied. To avoid this problem, both crop rotation and product rotation are recommended.

It is also recommended that you use a mix of herbicides from at least two different groups to target the same weed. The reason being that, if a weed has a gene that is resistant to one herbicide group, it will be eliminated by the second.

Examples of rotation crops and herbicide mixes:

Corn: herbicide from group 9 (Glyphosate) and group 27 (Callisto)

Soy: herbicide from group 14 (Valtera) and group 5 (Metribuzin)

Grains: herbicide from group 6 and 4 (Buctril M) and from group 1 (Puma)

Use a pre-emerge herbicide

A pre-emergence herbicide targets weeds before they emerge. In fact, the weeds are killed at germination, when they hit the herbicide barrier.

Important: The product will not affect already emerged weeds, nor those that germinate later in the season.

  • Applying the treatment

The treatment is applied before the young soybean shoots begin to break through the soil, namely before seeding, or 3 days after. It then takes between 0.5 and 1 inch of rain, depending on the product, to activate it. By activation, we mean that the herbicide must be thoroughly mixed with the soil, to create a protective layer.

At the time of application, make sure the herbicides are thoroughly mixed and evenly spread throughout the desired area. Remember to read the manufacturer’s instructions, follow the recommended doses, and calibrate the sprayer correctly!

Roll the soil

In addition to improving the contact between the seedlings and the soil, rolling the soil flattens it and breaks up any dirt clods. It also prevents moisture evaporation, resulting in a fresh soil bed for sowing.

Use a spiked chain harrow

The spiked chain harrow eliminates weeds that germinate early, either before or during tillage. With each pass, the spikes vibrate, uprooting the radicles od unwanted weeds.

Following application of a pre-emerge herbicide, harrowing with a spiked chain harrow is recommended if there is no rainfall within 7 days following the herbicide application. Harrowing helps mix the herbicide into the top few centimeters of soil to maximize its effectiveness.

So that’s our blog. Happy weeding and be sure to talk to our soybean experts if you have any questions.