Get Post-Emergence Treatments Done Early

Jun 12, 2014

Paul O. Johnson
Weed Science Coordinator

Early application of post-emergent chemicals before weeds are too large will insure good control of that flush of weeds. The thing that has changed with resistant weeds is when old chemistry or non-glyphosate control is used large weeds are not as likely to be controlled. The weeds will compete with the crop for nutrients, moisture, and sunlight.

In the past with glyphosate type products some people waited for all weeds to be up before spraying. If the weeds were not heavy this worked and did not have a large effect on yield. However, with non-glyphosate chemicals, weed size and crop size both have to be considered when making spraying decisions. The rule of thumb that is used now is “early is just about always better than late.” Even if you have some late emerging weeds they will not have a large effect on yield but could still increase the weed seed bank for next year. With just using other chemistries there may be a few weeds left in the field because the chemical used may not cover all types of weeds in the field.

The last thing to remember is if it is wet and humid in the field avoid using the methylated seed oils as they could cause more crop response than desired in wet conditions. Usually if plants are growing well with moist conditions a surfactant is desirable. Always read the label to determine the right additives and also remember some of the old chemistries do not require the addition of any additives.

Source : SDSU

Video: Winter Canola Trial in Mississippi | Can It Work for Double Cropping? | Pioneer Agronomy

Can winter canola open new opportunities for growers in the Mid-South? In this agronomy update from Noxubee County, Mississippi, Pioneer agronomist Gus Eifling shares an early look at a first-year winter canola trial and what farmers are learning from the field.

Planted in late October on 30-inch rows, the crop is now entering the bloom stage and progressing quickly. In this video, we walk through current field conditions, fertility management, and how timing could make this crop a valuable option for double-cropping soybeans or cotton.

If harvest timing lines up with early May, growers may be able to transition directly into another crop during ideal planting windows. Ongoing field trials will help determine whether canola could become a viable rotational option for the region.

Watch for:

How winter canola is performing in its first season in this Mississippi field

Why growers chose 30-inch rows for this trial

What the crop looks like as it moves from bolting into bloom

Fertility strategy, including nitrogen and sulfur applications

How canola harvest timing could enable double-cropping with soybeans or cotton

Upcoming trials comparing soybeans after canola vs. traditional planting

As more growers look for ways to maximize acres and diversify rotations, experiments like this help determine what new crops might fit into existing systems.