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This was the year that not using residual herbicide at planting shows. Some farmers got the seed in the ground, but either did not apply a PRE or rains prevented them from applying it. And, unfortunately, there are still too many growers hoping that their post application would work.

For several years now we have been telling growers to apply a PRE as a practice to manage weeds resistant to herbicide. And some of them have adopted this to deal with the threat of not being able to manage waterhemp and Palmer that are resistant to glyphosate.

But for much longer weed scientists have been telling us to apply a PRE at planting so you could delay your POST until later in case rain kept you out of the field. Based on the number of fields I see with tall weeds, this message hasn’t sunk in.

So what am I seeing during my drives?
• There are fields of beans with ragweed and waterhemp over knee high that won’t be controlled regardless of what you do at this late stage
• And fields treated with residuals are really performing

There are a number of good residual products you can put down at planting including Afforia®, Anthem®, Authority® products (Assist/Elite®/First™/Maxx™/MTZ™/XL), Boundary®, Envive®, Fierce® and Fierce XLT, Optill® Pro, Pummel™, Prefix®, Torment®, Trivence®, and Valor® XLT. Got a weed problem this spring that a residual would have controlled? Get familiar with the products your retailer is handling and plan to use it next year.

The big question is what you can do now that weeds are getting too tall. You can apply a tank mix of Flexstar and Cadet® along with glyphosate, but you have to cut that off by July 15 so it doesn’t carry over to next year’s corn crop. You can still apply Cobra, but remember it has a 45-day preharvest interval. And there are other product choices available.

I know it might seem late to spray with tall weeds, but if it turns dry go ahead and spray. It is better to spray and kill what you can than do nothing at all, lose the crop and have the weeds go to seed. Just remember that with the soybean canopy present it is hard for herbicides to penetrate the canopy and get control, so you will just have to tolerate the escapes.

If you don’t use a PRE with soybeans, let 2015 be a lesson that says you should.