FRUITA — The flowering tamarisk trees have a 150-year head start, but by next year, there’s a good chance that tiny insects will have made “significant impact” in Mesa County in eliminating the nonnative trees, said John Heideman of the Tamarisk Coalition — a group formed in 1999 to combat the proliferation of tamarisk trees.

Tamarisks were introduced to the United States in the 1850s from Eastern Europe and West Africa. The trees, which bloom all summer long, were used as ornamentals and to stabilize stream beds.

Tamarisk trees eventually escaped cultivation and got into river systems, where the plants have competed unfairly with native cottonwood and willow trees. Tamarisks have a deep root structure that can reach down to 100 feet, whereas most native water-loving plants have a shallow root structure of 8 to 10 feet. Tamarisks also spread their seeds all year long, unlike other species.

“Anytime a rain storm comes, the seeds multiply,” Heideman said.

Tamarisks also out-compete native species because they fare well in highly saline soils, Heideman said.

Also, “none of the bugs that preyed on it, came with it,” said Heideman, who spoke to a Friends of McInnis Canyons gathering Tuesday at the Hot Tomato Cafe in Fruita. Heideman talked to the group about efforts to rid McInnis Canyons National Conservation Area of the invasive trees.

Volunteers with the Tamarisk Coalition have hiked into Flume, lower Devil’s and Pollock Canyons 15 times in the last three years to cut down and haul out tamarisk trees. Stumps are treated with herbicides to prevent the trees from growing back.
Another form of attack are leaf-eating beetles that have been introduced to the National Conservation Areas Knowles, Flume and Horsethief Canyons.

Beetles, imported from China, were first released in Utah four years ago, where land managers have seen success in combating tamarisk growth in several Utah counties.
“Biological control is reuniting the insect pest with the host plant,” Heideman said.

Heideman seems frustrated that it took so long to get approval to use the bugs to tackle the tamarisks.

“Most biological control agents take five to six years to be approved by the USDA (United States Department of Agriculture),” Heideman said. “The tamarisk leaf beetle took 20 years to get approved.”

When willow trees lost habitat to tamarisk, the southwest willow flycatchers, an endangered species, started nesting in tamarisk, and so tamarisks were declared critical habitat for the birds.

But “common sense would tell you if you get rid of the tamarisks, the willows will grow,” Heideman said.

Seventeen states have joined the Tamarisk Coalition. Its board of directors include representatives from Kansas, Colorado, New Mexico, Texas, Utah, California and Montana.

The Friends of McInnis Canyons was formed in 2005 to promote stewardship of the natural, recreational and paleontological resources in McInnis Canyons NCA, said president John Howe. Members provide financial and volunteer support in maintaining trails, enhancing wildlife habitat, and fund research and educational programs.

About 40 people attended the Friends spring mixer at the Hot Tomato, including charter board member Warren Gore who was presented with a framed picture of McInnis Canyons.

The McInnis Canyons NCA is located west of Grand Junction and mostly south of I-70, reaching as far as eastern Utah. The NCA includes 122,300 rugged acres of sandstone canyons, natural arches, spires and alcoves carved into the Colorado Plateau along a 24-mile stretch of the Colorado River. The McInnis Canyons NCA includes 75,550 acres of wilderness designated as the Black Ridge Canyons Wilderness.

Reach Sharon Sullivan at ssullivan@gjfreepress.com.