It is very difficult in a workshop of this nature to say something new and different. The secret, I understand, is to be early on the agenda. Here I am, right before lunch. Aside from that, I have been in Nevada for only a year. I defer any expertise on the subject to the earlier speakers. Particularly, in Nevada, Drs. Stan Smith, Dale Devitt, Jim Young, Sherm Swanson, and Wayne Johnson are the men who have contributed most recently to the ecology and habitat issues facing the state in regards to saltcedar encroachment.
You have seen the pictures of the Virgin River, the Colorado River, the Muddy River, Lake Mead, the Pecos River, and the Salton Sea. I'm sure we could all say in unison that we have an ecological problem of enormous proportions. But I submit to you that the greatest problem we as researchers and managers are facing is not where saltcedar has already established itself but on the leading edge of the invasion.
In the 1960's tamarisk encroachment was a dark cloud on the horizon seen and warned of by a few insightful forecasters. As the storm began to build, those who dealt with the effects of the invasion on a daily basis began to do studies and hold workshops. Now the storm is close enough to see that there is hail, lightening, high winds, and that there is cause for alarm. But the alarm needs to be sounded at the front. There is still hope for preventing serious ecological damage in places where saltcedar has not yet dominated the landscape.
Arid environments, as represented by most of the State of Nevada, may seem an unlikely place to wage an environmental battle but this state's riparian areas are rare and precious commodities. Only a few percent of the state of Nevada is classified as riparian yet the vast majority of the state's biodiversity and economic base depends upon those areas. Southern Nevada's riparian contribution to the Colorado River watershed and the rivers and streams of the Great Basin represent habitat for more than 75% of the vertebrate species found in Nevada. The majority of the riparian areas in the state are privately owned but most have specially designated, or agency-cherished riparian lands, as well. Furthermore, every human population center in the state, except for some mining towns, is directly associated with a perennial water course.
In the north, the Stillwater National Wildlife Refuge has received some control effort on its 1,500 infested acres. It is hemispherically recognized for the wetland's importance to migrants of the Pacific Flyway. Unfortunately, it is connected to the Carson Sink which is dominated by saltcedar. The Humboldt Sink was also once a valuable resting and nesting site for waterfowl. Now, over 14,000 acres are infested with saltcedar. NRCS officials estimate that more than 60% of that sink is total saltcedar canopy cover. Another 6,000 acres of the Humboldt River and associated reservoirs are impacted. Further, the Carson, Walker, and Truckee River drainages total approximately 25,000 acres of saltcedar dominated riparian area. The numbers are staggering. We, the State of Nevada, along with public and private land managers must begin to expend some effort and finances toward saltcedar control measures.
While this conference is focused on wildlife habitat loss and reclamation, some of the impacts on human habitats and economies should also be noted. Recognizing the shared impacts, helps us build coalitions based on shared interests and mutual concerns.
Wildlife and habitat managers in the state need to build coalitions and get "buy in" from every party involved. Taking into account the ultimate users and financiers of our efforts to control saltcedar, there is some serious work that needs to be accomplished in Nevada.
In the last few years, there have been some steps taken in the right direction. Senator Harry Reid has become concerned about the saltcedar issue in Nevada and around the region. He was instrumental in the decision to allow a controlled release of Diorhabda elongata (Chinese Leaf Beetle) in the Humboldt Sink. Dr. Jim Young of the USDA-ARS has been experimenting with chemical control measures for the past five years. Drs. Devitt and Smith of UNLV have been on the leading edge of research in saltcedar ecology and rates of evapotranspiration and soil salinization . The Southern Nevada Water Authority has contributed significant financial support for inventories and research along the lower Virgin River and the Lake Mead National Recreation Area. With the work at Ash Meadows as a model, several entities have attempted habitat restoration following intensive saltcedar control.
Northern Nevada has become a large laboratory for answering questions such as: "What are the invasion mechanisms?" "What is saltcedar's potential beyond its current distribution?" It is already on the class C noxious weed lists in Oregon and Washington. It is showing up on the tributaries of the Snake River in Idaho. Is saltcedar headed north? Literature suggests the altitude limit of the invasion is around 5400 ft. I have seen it near Lovelock at well over 6,000 ft. Where will it stop? What are its altitude limits in a warm, arid environment?
Recently I was in the Trinity mountains about 10 miles outside of Lovelock. Early that morning I had seen antelope, coyotes, jackrabbit, and wild horses. Later I came upon a lone tamarisk tree I will guess was nearly 30 years old. There were no young trees nearby but another mile away, further up the wash was a seep that had obviously seen some heavy wildlife traffic. At the mouth of this wet draw was the usual contingent of willows, grasses, and sedges along with about a dozen 2-3 year old saltcedar bushes. Was the 30 year old tree the source of seed for the younger bushes? If so, was the older tree also the source of seed for the saltcedar trees in the valley below which were probably the source of seed for the current 14,000 acre saltcedar mess the Humboldt Sink finds itself in today? An hours work and 10 dollars 20 years ago could have prevented the expenditure of millions of dollars it will take to restore the sink to its pre-saltcedar condition and value. In 20 more years from now, will wild horses and antelope come to drink from that spring high up in the Trinity Mountains? Will there be any waterfowl nesting in the Stillwater Refuge?
Nevada's perspective on habitat loss is simple. We don't have any habitat to waste. We don't have any water to waste. We don't have any other places to live. Nevada needs to control this invasion by working the upstream, leading edge of the invasion. We want to be a barrier between the tamarisk invasion and the Pacific Northwest. We are asking for the mandate, the resources, and the tools to do the job.
Return to Workshop Home Page or continue on to the next paper "Mapping Saltcedar Using Spatial Information Techniques: Just How Much Saltcedar Is There?"
For information on the outcome of this workshop or integrated weed management in the Pacific Region (Region 1), U.S. Fish and Wildlife Service, Portland, OR, contact: Scott_Stenquist@fws.gov
Conference proceedings hosted by the National Invasive Species Information Center