What is in this article?:
- Rains bring heavy weed infestations and pigweed problems.
- No silver bullet
- Different approaches
Pigweeds can grow extremely fast when resources are available so thorough and timely scouting has been key in order to stay on top of the issue.
Resistant pigweed calls for a more diversified weed control strategy.
By this time of year most fields have progressed enough that broadcast over-the-top applications may not be sufficient for effective coverage or product labeling requires a different approach. That’s where hooded sprayers come in.
Hooded sprayer applications can be a key to finishing the season in satisfactory condition. Regardless of the herbicide program, using a hooded sprayer effectively requires a certain amount of understanding. Most have heard of or experienced the detrimental effects that speed can have on broadcast applications. Slowing down when using a hooded sprayer is twice as important compared to broadcast applications.
Good coverage is essential and several things are necessary to ensure adequate coverage. First, make sure the targeted spray volume agrees with the product labeling. Most products applied under a hood do not perform well at low volumes. Secondly, learn to treat this application or trip like you’re cultivating 1 to 2-leaf cotton.
Slow and precise is the preferred mode of operation. This is a hard pill to swallow in the age of monster booms and 20 mph ground speed capabilities. While many have built operations on the premise of no-till farming, speeds such as this will be a definite change of pace. Traditional post-directed or hooded sprayer treatments (Aim + Direx, Aim + Caparol, etc.) that are effective at helping to burn down late flushes of weeds may also injure cotton if not used properly (some have height requirements, some have cotton stem bark requirements, some have both).
These products are not intended to contact green cotton stem tissue. However, when used properly they do a great job.
Reading the product labeling is mandatory. Several herbicide program options exist for hooded sprayers and each one has its own set of guidelines. Regardless of the production environment (conventional, minimum, strip-till or no-till) yellow herbicides can still be applied through hooded sprayers later in the season with beneficial results. Granted, without overhead irrigation or rainfall, mechanical incorporation may be required to activate some of these products.
While tank-mixing with glyphosate has been highly recommended for the prevention of GRP, it may not be the program of choice with resistant pigweed in the area. Also, we need to remember that some tank-mix partners (Warrant, Prowl H2O, Dual) provide no additional burndown activity and therefore the entire burden of controlling emerged weeds falls solely on glyphosate.
Due to the number of producers experiencing pigweed control failures with glyphosate this year, some of the more traditional alternatives (previously mentioned) should be seriously considered.