Invasive grasses found in Sheridan County

Home|Outdoors Feature|Invasive grasses found in Sheridan County

Two new invasive annual grasses, Ventenata and Medusahead, have recently been discovered in Sheridan County. Ventenata and Medusahead are native to the Mediterranean. They were first discovered in the United States in the Great Basin area. 

Since their introduction, they have shown to be highly invasive, taking over native rangelands and forming large monocultures. Until recently, these grasses were not thought to be in Wyoming. With this discovery, land managers are working to control and limit their spread to other areas of Wyoming. 

So, how do invasive annual grasses affect the sportsmen? One way is the reduction in quantity and quality of forage available to wildlife. As important wildlife ranges are invaded with annual invasive grasses, availability of forage decreases, which can lead to a decline of game animal populations over time. Invasive annual grasses germinate earlier than native plants, robbing native plants of soil moisture needed for germination, and are much less palatable to wildlife. 

Another way invasive annual grasses can affect wildlife is by the increased chance of wildfire burning important habitat. Since invasive annual grasses germinate earlier, they also cure out faster, thus creating a fine fuel load earlier in the year that increases the risk of early wildfires. Although wildfires are part of the natural ecosystem, and can benefit wildlife, areas that have high densities of invasive annual grasses burn more often. 

Due to their affinity for disturbed landscapes, invasive annual grasses quickly reestablish on burned sites and can become the dominant species.

The Wyoming Game and Fish Department is very concerned about the effect invasive plants can have on our wildlife and their habitat. In the last three years, Game and Fish has spent a total of $2.5 million on invasive plant treatments throughout the state in important wildlife habitat. With the discovery of Ventenata and Medusahead grass in Sheridan County, there is now the risk of new invasive grasses affecting wildlife habitat in Wyoming. Fortunately, these grasses have not been discovered outside of Sheridan County.

Sportsmen recreating in Sheridan County can aid in reducing the spread of Ventenata and Medusahead grass to other areas in Wyoming by cleaning clothes, trucks, recreational vehicles and hunting dogs every time they leave the field.

By limiting the spread of these grasses, we can protect other important wildlife habitats in the state from being invaded and possibly even eliminate these grasses from the state of Wyoming.

On Aug. 24, the Wyoming Game and Fish Department and the Sheridan County Weed and Pest will host a workshop to educate hunters about what they can do to limit the spread of invasive plants.

The public workshop will start at 5:30 p.m. at the Wyoming Game and Fish Regional Office in Sheridan, located at 700 Valley View Drive.

Participants are encouraged to bring proof of a valid 2017 hunting or fishing license to receive a token for a free car wash donated by Buggy Bath Car Wash.

We hope to see you there!


Todd Caltrider is a Wyoming Game and Fish Sheridan Region terrestrial habitat biologist.

By |August 11th, 2017|

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