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Now is the time to plan your 2015 weed control

Julie Sievert, Extension Educator

September 13, 2014

With a chill in the air that feels all too much like autumn is upon us already, it's a great reminder that the 2014 growing season is coming towards its conclusion. Most farmers who harvest small grain have it in the bin already, and the straw is packed neatly in sheds and bunkers. As we are preparing to harvest that last cutting of alfalfa and then on to silage and corn grain, it's easy to get caught up in the busyness that is farming to put off planning for 2015 until the combine is parked in the shed. However, now is a great time to get started planning for next year's cropping decisions – and weed control is a very important part of that picture.

First, scout your fields. There really is no substitute for getting out in your fields, getting a little dusty, and getting a good visual of what is out there as far as weeds. Bring along a notebook or field map, and make notes or drawings of weedy problem areas. Pay attention to the perimeter of the fields, especially next to ditch banks and groves, where weeds may be harbored. By making this an annual habit, you will have a good long-term picture of what's going on in your field. "Was this patch of velvetleaf here last year? I don't remember it. But maybe I did see a plant or two..." The goal is to nip the weed problem in the bud by recognizing a small patch before a full blown outbreak happens.

Identify any weeds that you don't recognize. Sure, most of us know the common ones – ragweed, waterhemp, lambsquarter, and velvetleaf. However, those aren't the only problem weeds out there. When selecting a herbicide, it's incredibly important to know if that herbicide will be effective against the weeds that you have on your property, and that really shouldn't be made into a guessing game. Pick a full stem with leaves of your weed or else take some good, clear pictures. Remember to take pictures of the leaves, stem, and seed head or flower if it is present. If you have an Agriculture Educator in your local Extension Office, he or she can be a great resource for identifying weeds that you are unsure of. The Farm Information Line at the University of Minnesota is a great resource if you do not have a local Agriculture Educator in your county. Pictures of your weeds can be emailed to for identification. The Weed Science Society of America has some weed identification tools on their website as well and can be found at

Talk with your agronomist now about the weed problems you've seen in your field this year. If you think you have herbicide resistance in your fields, communicate this to your agronomist, so he or she can help you choose an alternate herbicide. Remember, the more information you give your agronomist, the better he or she is equipped to help you. In many instances, a pre-emergence herbicide will be a good investment for next spring's weed control.

In addition to scouting crop fields, now is a great time to scout pastures and pasture perimeters as well. Perennial weeds are moving energy down into their roots during the fall season to create reserves so they can return next year. This means fall is a perfect time to get perennial weeds under control by mowing them and using an effective herbicide. Again, if you are dealing with weeds you don't recognize, get them identified before planning your mode of attack so you are using the most effective strategy possible.

While I hope your weeds are few and far between, every farmer has to deal with weeds. By taking some time now to scout your fields, identifying any questionable weeds, and planning your weed control for next year, hopefully you can minimize your weed challenges. Use your local Extension office or the Extension Farm Information Line for help with weed identification. Remember, one year of poor weed control can mean years of problems dealing with a large weed seed bank in your field.

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