Crop Talk – Residual corn herbicides

A cool, wet weekend dropped soil temperatures. Recently planted corn will not be very active until our soils begin to warm up again.

Weather Update:

  • Soil temperature at 2″: 48° at 10:30 AM
  • Rainfall: 0.1″

This week is all about corn herbicides – residual in particular. RoundUp and Status are very common herbicides in our part of the country, but neither provides anything in terms of residual weed control. Here are a few of my favorite products:

Atrazine is probably the most well-known residual herbicide around. It is very strong against grasses and handles broadleaves such as kochia and lambsquarters. I like it primarily as a dryland option because it is very economical and also to avoid any potential rotation issues. Tank mix with RoundUp to burn-down any emerged weeds.

Trisidual is a great option for irrigated corn. It can be applied on corn from pre-plant all the way up to 11″ tall. In most cases, the residual activity lasts long enough to make it through to canopy, making it a great one-pass option with a price comparable to RoundUp/Status. Rotation to dry beans is no problem for the following year, but sugar beets can’t be planted for 26 months.

Zidua is the only choice if you have Palmer Amaranth creeping into your corn fields. It hasn’t become very common in our area yet, but if you see it, I strongly recommend getting it under control before it spreads. Palmer is a prolific seed producer and will quickly multiply in your fields, not to mention having resistance to many herbicides including RoundUp.

As usual, visit with your local Farmer’s Coop agronomist if you have any questions.

Make it a great week!