Noxious and Invasive Plants

Nevada has many noxious and invasive weeds that occur throughout the state. Most of these weeds came from regions that have a compatible climate with Nevada such as eastern Europe and western Asia. Many were introduced by humans, both accidently and intentionally. For instance, cheatgrass is believed to have arrived in the west as a wheat seed contaminant. Salt cedar or tamarisk was planted along streams for erosion control and purple loosestrife was planted in gardens because of its pretty purple flowers.

Noxious and invasive weeds are more competitive than native plants. Tall whitetop, for example, produces thousands of seeds each year. Some of these seeds can survive in soil seedbanks for up to ten years. In addition, tall whitetop can reproduce plants from its rhizomes which are underground stems with buds, and its roots can reach 20 feet deep. Cheatgrass seeds germinate in the fall and grow to maturity in very early spring without competition from other plants. In addition, it reproduces rapidly following a fire before other native plants can reestablish. Once established, weeds can spread in many ways: by humans, birds, livestock, wind, or by hitchhiking on vehicles.

Noxious and invasive weeds have economic impacts because they are expensive to control and they can reduce agricultural production, property values, and water availability. Prevention is the most effective treatment for noxious and invasive weeds.

Don’t let noxious and invasive weeds become established. Here are some things you can do to help:

• Drive on established roads and trails.
• Learn the difference between noxious and invasive weeds and good plants.
• Be cautious of new varieties of flowers that will “grow everywhere.”
• Some weeds are colorful and it’s tempting to pick them. Don’t be fooled. You’ll be spreading their seeds to new areas.
• When using pack animals, take certified weed-free feed with you. Feed your animals weed-free hay for at least 96 hours before entering back country areas. Brush your animals well before leaving the back country.
• Wash vehicles, including the undercarriage and wheels, if you have been off-road or in a weed infested area. Weed seeds will lodge between the tire treads, behind the license plate, and in cracks and crevices you can’t see, and travel hundreds of miles before falling off. Dried mud can be seed banks for weeds. Spread the word, not the weeds!