Marking, and Measuring, Success

Tackling a huge project, such as the removal of dangerous invasive plants, particularly tamarisk, requires planning, commitment, and patience. It also requires tracking progress, to demonstrate success and keep volunteers and the community on board. Thus, the resounding success of DPI’s biggest project to date is cause for celebration and calls for a continuing effort to protect native habitats from invasive species and to reduce wildfire risk.

Since December 2023, 30 DPI volunteers contributed some 1,500 hours to clear five acres of tamarisk. While the physical effort has been substantial, the results have been dramatic. Within the project area, between Cactus Gulch Court and Wisteria Way where fire risk to homes was highest due to the enormous fuel load, the destruction of native habitat by the invasion of tamarisk was striking.

“We found dead cottonwood trees, two to three feet in diameter, which likely were killed by the invasion of water-consuming tamarisk,” reports DPI President Chuck Warren. “No native plants have survived inside what became a monoculture of this invasive plant/tree. The size and density of tamarisk invasion suggests that considerable water was present in this area in the past and may now be available for the return of natives.”

This massive project is but one of 35 that have been completed in the 3 ½ years since DPI was founded. Warren estimates another 300 to 400 hours of work will be required to finish removal of tamarisk in this particular area alone.

As part of its mission to permanently remove invasive plants, DPI begins monitoring removal areas for tamarisk regrowth within three months after a project has begun and continues to monitor the site for up to two years. If regrowth appears at nine or twelve months, the monitoring visits continue until two 3-month intervals show no regrowth. Given the great expanse of infestation that had been visible to homes [with debris piles left to decompose in time] cottonwood and mesquite trees were planted, adding to surviving trees and adding to the force of native species now naturally advancing into tamarisk dead zones.

“Good things happen when people work together and support each other in a mission to preserve the desert ecology and reduce fire danger,” says Warren. Clear results include new access to space for trails and recreation that was previously blocked, increased diversity of plants and animals, and reduced fuel load for wildfires, which has become an on-going issue as insurance companies raise rates and threaten cancellation of coverage for homeowners. “And certainly of significance is the development of relationships and connections with others in the community and city,” Warren adds.

Although the work of DPI has made a tremendous difference in our community, the invasion of tamarisk in southern Utah requires on-going vigilance. What can be accomplished requires not only time and physical effort but also financial support to cover operating expenses and the costs of purchasing and maintaining the equipment—saws, clippers, a chipper, and herbicide applicators—used in the process. Unfortunately, federal funding cuts threaten a promising grant for which DPI has applied that would open the door to hiring small crews to advance its work.

If you believe in this mission and would like to help celebrate DPI’s success to date, your financial support would be most welcome. Visit our website at www.desertpi.org or contact Chuck Warren at [email protected] or Vice President Dan Beck at [email protected] if you are willing to donate and/or volunteer to support this effort.