Water Department
The Monitor 1998
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Saltcedar Control Program Brian Cashore, Saltcedar Control Project Coordinator When tamarisk or saltcedar was intentionally introduced into the U.S. in the early 1900s it was merely one of many non-native ornamental nursery plants that were transplanted around the globe. What makes non-native invasive plants such as saltcedar different from other introduced species is their ability to take advantage of disturbances to the native plant community to expand their limits. Once established, non-native invasive plants can spread rapidly because of the lack of natural enemies that keep plant populations balanced in their native range. Even though plants, animals, and other natural organisms continually change and expand their territories, the pace of the changes caused by human disturbance is unprecedented.
In the Western U.S., disturbance came in the form of an increasing human population and the water diversions, manipulations, and dam building that resulted. In the Owens Valley, much of the valley floor was disturbed when the Los Angeles Department of Water and Power constructed a series of dikes and basins to contain the abnormally high runoff in the late 1960s. Before that, saltcedar was only a minor component of the valley's plant composition. In 1998, the Inyo County Water Department increased its efforts to curb the spread of saltcedar by hiring a seasonal saltcedar eradication crew and setting up a program of systematic tamarisk control. Three seasonals, Bruce Klein, Chuck Spresser and Bryan Taylor joined Rick Puskar and myself in the effort to contain and control the spread of saltcedar while working towards the denser populations in the central portion of the valley. Though labor intensive, the technique of manually cutting the trees with chainsaws and loppers and immediately treating only the cut stumps with an environmentally safe herbicide is highly effective and less destructive to the landscape than some other forms of invasive plant control. Eventually, other techniques such as controlled burning and biocontrol using insects will be incorporated into the program. At each work site, a data sheet is filled out and the location is recorded using a global positioning system (GPS) so that future monitoring and follow-up treatment can be undertaken. The saltcedar crew worked on sites from north of Bishop to south of Independence cutting plants ranging in size from 1/4 inch to 18 inches in diameter. Much of the work along the Owens River involved crew members walking along the river banks with chainsaws cutting and treating trees, then meeting our truck at an accessible road downstream. At one irrigated site, the crew worked for 9 days cutting an area of less than 3 acres that produced over 35 cords of cut tamarisk wood, 3 cow carcasses, and countless rat nests. It took a 15-man CDF crew over two weeks to clear and burn the slash at this location. Because the core area of saltcedar is located within the lower Owens River area, approximately $1 million of a $3 million grant to rewater the river has been allocated specifically for the saltcedar control program. The expanded crew and program will make it possible to increase control efforts prior to the rewatering associated with the Lower Owens River Project. The end of the 98/99 field season culminated with the taking of Black Rock Springs Hill along the dry river channel near Black Rock Fish Hatchery. Looking north from this vantage point, we saw the dry Owens River bed free of saltcedar trees, ready for the Lower Owens River Project water releases. Looking south, we saw the red bark-tinged hue of a saltcedar-covered landscape, and next season's work. |
