NEW CASTLE, COLO. - A prolific tree that already slurps up more than twice the amount of water in the southwest desert as all the major cities of Southern California combined is the target of an eradication project from New Castle to Rifle in Garfield County.

Tamarisk, a non-native tree species, have quickly spread over much of the Rocky Mountain West and other areas, sending out water-hogging roots along all sizes of rivers, ditches and creeks, including the Colorado River, Alkali, Divide, Dry Hollow and Mamm Creeks.

County Vegetation Manager Steve Anthony outlined a three-year eradication project at the Jan. 28 Ag Day in New Castle, sponsored by the Natural Resources Conservation Service and several area conservation districts.

“We think we need to get a handle on this on anywhere from 300 to 500 acres,” he said. “Our suspicion is there’s a lot more Tamarisk in areas between the creeks.”

Project a three-way partnership

The county has partnered with the South Side Conservation District to get landowner permission along the creeks to send in State Wildland Inmate Fire Team (SWIFT) crews from the Rifle Correctional Facility to cut down and treat stands of Tamarisk and Russian Olive trees. Russian Olives also use a lot of water.

The successful removal of the trees takes three years, Anthony said. The trees are cut down, slash removed and the stumps treated with chemicals to kill them in the first year. The second year treats invasive weeds that sprout up. The area is restored and replanted with native trees that need much less water in the third year, Anthony said.

Mamm Creek is the most heavily infested with Tamarisk, Anthony said, so hand treatment with a SWIFT crew is too labor intensive.

Helicopters will be used to drop chemicals instead, Anthony said.

“We probably need 100 percent buy-in from the landowners on Mamm Creek,” Anthony said, due to the need to spray from the air. “It’s pretty solid for probably about five miles all the way from (Interstate 70) up the creek.”

The county can probably schedule the SWIFT crew for four to six weeks in the summer, he added, and last year the crew completed around six projects.

Silt Mesa couple pleased at results

Kathie and Tony Barrie had Tamarisk and Russian olive trees removed from part of their 134 acres on Silt Mesa last year. Some of those trees were 25-30 feet tall, Tony Barrie said.

“It took them about a half day to do the work,” said Kathie Barrie. “We had about an 80 percent kill rate. It was really very good.”

The couple praised the SWIFT team for their hard work and courteous, professional approach.

The Barries paid $125 for the herbicide to apply to the tree stumps, Tony Barrie said.

“That was a great deal for us,” Kathie Barrie said. “We’re at the top of a watershed and we couldn’t do the work ourselves because of the time element. So we’d recommend them to anyone.”

Eradication is the goal

Brett Jolley is with the South Side Conservation District and said the goal is to start as far up the creeks as possible and work down toward the Colorado.

“We want to try to completely eradicate the Tamarisk,” he said. “We’ll have to see what can be done. If we don’t start now, it will completely take over the creek banks in about 20 years.”

The county pays 100 percent of the cost of the crew, landowners pay for the chemicals or herbicides, remove the slash, do the follow-up treatment and restore the treated area, Anthony said.

Landowners pay up to $50 per acre and the rest is paid by the county and the conservation district, Anthony added. The county commissioners agreed to spend $75,000 on the project.

“If we can do this in a cooperative effort, we think we can get a significant increase in water flows in the creeks,” he said. “Plus we’ll improve wildlife habitat by getting rid of all those thick tree stands.”

Landowners interested in participating in the project can call the NRCS at 945-5494, ext. 105, or Anthony at 625-8601.