My Story 5: Whitetop: An Effort to Help Restore the Truckee River System of Northern Nevada
Over the past 20 years the spread of invasive weeds in the area of northern Nevada known as the Truckee Meadows has increased dramatically. Cooperative Weed Management Areas (CWMAs) have been established throughout the state to address these conditions. While there are a number of invasive species threatening Nevada’s wetlands, tall whitetop (Lepidium latifolium) has proved particularly harmful along the Truckee River. Tall whitetop is native to Europe and is thought to have originally been brought to this country mixed with hay. The Truckee River, which flows through the Truckee Meadows in western Nevada to the Pyramid Lake Indian Reservation, contains scattered infestations of tall whitetop throughout the entire river system. Until the late 1990s the weed was a nuisance in the area but was considered manageable. The floods of 1997 accelerated the spread of tall whitetop dramatically however, and turned the infestation into a catastrophe. Since then the Truckee River System "has gone from a mostly healthy terminal river to a breeding ground for tall whitetop," according to Tina Kadrmas, coordinator for Cooperative Weed Management Areas in Nevada.
Tall whitetop spreads rapidly and encroaches on the native plant community. This leads to increased erosion, increased sedimentation in waterways, and reduction of fish and wildlife habitat. Cooperative Weed Management Areas in northern Nevada continually monitor the land along the Truckee River and track the spread of the weed in order to establish management strategies. Test areas have been established to study the feasibility of different chemical control methods as well as biological control methods such as grazing by goats. Thus far, chemical treatment followed by replanting with non-invasive species has been the most successful method for controlling tall whitetop.
Although some areas have been successfully treated, only minor progress has been made in controlling the overall infestation due to the extent of the area affected. Coordinating control efforts on public and private lands also presents a challenge. Land which has been successfully treated can quickly become reinfested if neighboring land is not also being treated. A state weed map created by the cooperative efforts of government agencies provides good information about the location of infestations on public lands but state weed coordinators have only sketchy data about weed infestations on private lands. Persistent funding to support long term maintenance treatment is also needed. Studies by the University of Nevada Cooperative Extension on the economic impact of treating tall whitetop have determined that small-scale control projects cost about $12,000 but that delaying treatment for ten years increases that cost to $79,000. This is just a small portion of what would be necessary to manage tall whitetop along the entire Truckee River, which runs about 100 miles through northern Nevada.
Ideally, the goal of managing land infected by invasive weeds is to return the land to its native state. However, this is not always possible given the time, money and manpower required. Even when other resources are available native species for replanting may not be obtainable. Tina’s goal for land management in northern Nevada is to establish a mix of non-invasive plants, including non-native species when necessary, that are able to support water quality and erosion control, and combat encroaching invasives. Cooperation between private citizens and public agencies is essential to efforts to eradicate or even control tall whitetop in northern Nevada. Tina would like to see local groups, including private landowners, adopt the Truckee River corridor from Reno to Pyramid Lake in order to support weed containment and management efforts. "Provided with the necessary teamwork and economic resources," she says "we can bring this land back from the verge of destruction to a state of relative health and prosperity."