October 6, 2021

Noxious Weeds and Hay

Hay bale

As we approach the winter season, those of us who have been working hard planting, irrigating, and harvesting crops, are welcoming a small break. On top of the care and time that goes into field crops, managing noxious weeds is another thing that a lot of us are ready to take a break from in the current year. Although we may be tempted to put weed control out of our minds for the season, now is not the time to forget about noxious weed management. Some specific management strategies we use this winter can have a large impact on the amount of noxious weeds we will have next year.

Let’s discuss hay. Often times, especially in our beef operations, we feed and scatter hay across our fields to sustain our cattle in the winter. At times, the hay we feed could be full of noxious weed seeds. After the cattle eat and tromp through the hay and snow, those seeds reach the soil. With the extra moisture from the snow, an ideal habitat is created for those seeds to sprout in the early spring. One specific weed that I have become concerned about with is Annual Kochia. I have seen a few producers harvesting what appears to be a field purposefully planted with Annual Kochia. Although Kochia is not listed as a noxious weed, it can still be very troublesome within Cache County. Another concern is Dyers Woad. The seeds from this noxious weed can also be spread through contaminated hay. Here are a couple strategies to avoid letting noxious weeds sprout in your pasture.

First, make sure that your grass pasture healthy. In fact, often the best weed prevention strategy is a lush, healthy pasture. To keep grass pastures lush and healthy, it is vital to avoid overgrazing. Follow the “leave 4” rule meaning you leave at least 4” of grass post-grazing. It is also important to irrigate and fertilize pastures to give them the best resources possible. For dryland pastures this can be difficult. We often see an increase

in noxious weeds in dryland pastures due to lack of resources. Do the best that you can with resources available.

Second, identify what noxious weeds might be in your hay, or what noxious weeds you may have. I have resources that can help teach you how to identify noxious weeds or I’m willing to help identify weeds if I can get a sample (in person or picture) of the weed. By identifying the noxious weeds early, you can determine what threats are posed to your pasture and develop a management plan to get rid of those weeds early on. Another critical reason to identify noxious weeds is because some can be toxic to animals. Animals will often avoid poisonous plants in a pasture setting, but when the poisonous plant is in a hay bale it’s hard for our animals to differentiate. If you can, avoid buying hay with noxious weeds in it. It is important to look for and identify noxious weeds in hay. If you use hay without noxious weeds, half of your problems are already cared for. Unfortunately, after a drought year like we just had, annual weeds that thrived off the heat and low moisture can be hard to avoid in hay.


Jacob Hadfield

Cache County Extension office