Whether it’s a small hobby farm or a large scale farm, all farmers should be aware of the invasive species that can be growing in their fields. Just a few are Jimson Weed, Canadian Thistle, and Russian Knapweed. All are similar because they overtake overgrazed pastures, barnyards, and fields.
Jimson Weed is an important invasive for farming operations; it is poisonous to all livestock animals. Not only can it be a problem in underused fields, overgrazed pastures and in the barnyard, but it can also be a problem in crop fields, particularly soy beans. Farmers should be watch out for this plant and taking appropriate measures to make sure that it’s not present where animals are grazing. They will most likely avoid it because of the odor and taste, but in sparse pastures, they could be tempted to consume it if they are hungry enough. If the farmer is producing hay and silage they should make sure that all the Jimson Weed has been removed prior to harvesting because this can contaminate the feed, making the animals sick. The seed of Jimson Weed can contaminate grain which most commonly effects chickens. The use of herbicides is the most effective way to eliminate Jimson Weed, just remember to take proper precautions. Although many animals have gotten sick from Jimson Weed, it is more common for humans to get sick from this plant. Children especially because they think the flower is pretty and end up ingesting it.
Canadian Thistle is another common invasive species in fields. It reduces pasture capacity and forage as well as overtaking native species. It can produce up to 3,000 seeds annually and the seeds can last in the ground for up to ten years. This plant can be poisonous to livestock, but only in large quantities, therefore Jimson Weed is a bigger concern for the animals. This is a tough plant to get rid of, therefore a foliar herbicide plan should be used in both the spring and the fall. Stinger is a product that is relatively specific to thistles and knapweed that has been shown to be effective on this plant. Mowing before the flowers come out is also beneficial, but they plant can flower multiple times during the season. Pre-flower mowing just once will not help decrease the amount of plants. Farmers should also know that tillage stimulates growth and can cause more seeds to spread and more plants to grow.
Last but not least is Russian Knapweed. This stubborn plant is slow to start, but once it is established it can spread aggressively. It can produce up to 1,200 seeds per year. Livestock generally avoid this plant because of its taste but it isn’t good for them to ingest in hay. Horses are especially sensitive if they consume Russian Knapweed because it can cause a fatal neurological disorder that affects the muscles that allow them to swallow. This puts the horse at risk for starvation. To help remove this plant from pastures, herbicides can be helpful. Farmers can mow in two to three intervals before the seeds set to decrease seed and shoot production. They can also use deep cultivation to help eliminate this plant however do not use shallow cultivation.
These are just a few out of the many plants that can cause harm to field production as well as livestock. Farmers should be aware of these plants due to their effects on animals.
-Jess Holmes, CapMo PRISM Project Assistant