Quantcast
Get breaking news alerts via email

Click here to manage your alerts
(Francisco Kjolseth | The Salt Lake Tribune) Dead, browned tamarisk lines the banks of the Colorado River as efforts to eliminate the invasive species appear to be working. The small tamarisk leaf beetle, imported from China, is used to control the non-native and invasive tamarisk plant. Tamarisk was brought to North America as an ornamental plant and has displaced native vegetation along rivers in the West. The beetle was released in 2004 along the Colorado River in Grand County, upstream of Canyonlands National Park in an effort to knock back tamarisk.
Canyonlands National Park faces a thorny issue

As the imported beetles continue their assault on the shrubs, not everyone agrees with eradication of non-native species.

First Published Dec 26 2012 01:01 am • Last Updated Apr 08 2013 11:33 pm

Fourth in an occasional series examining issues facing Utah’s national parks.

Photos
At a glance

Five things not to miss at Canyonlands National Park

Sunrise or sunset at the Grand View Point Overlook in the Island In The Sky District.

A river trip on the Green or Colorado rivers.

Mountain biking the White Rim Trail.

Hiking to the Great Gallery pictograph panel in the Horseshoe Canyon Unit.

Visiting the Doll House, a collection of sandstone pinnacles, domes, hoodoos and tower formations accessed via a very rough 4-wheel-drive road or a 1,000-foot hike from the Colorado River.

For more information on Canyonlands National Park, go to http://www.nps.gov/cany/index.htm.

Brett Prettyman

Join the Discussion
Post a Comment

Canyonlands National Park • Larry Aberback studied the banks of the Colorado River in quiet reflection and then posed a question many of the others on the commercially guided float trip had silently wondered.

"What happened to all those dying bushes? Is it drought?" the elementary school teacher from New York City asked during a trip through Cataract Canyon in July. "It’s kind of sad."

Sad, in this case, is in the eyes of beholder. The dying stands of bushes are tamarisk — a non-native, invasive species from Eurasia introduced to the American West more than a century ago. Tamarisk has taken over the banks of many Western rivers and is particularly thick along the Colorado in Canyonlands.

People sitting in the raft next to Aberback had a totally different view of the dying bushes. As Westerners involved in the environment, they saw the defoliating of tamarisk as a step in the right direction to allowing the return of native species.

The question then remains: is the death of tamarisk sad or long overdue?

National Park Service officials say evidence of tamarisk along the river corridor dates back to the early 1900s. Pictures of tamarisk from 1914 show it was well established by then. Controlled flows from dams upstream seem to have helped the invasive species thrive starting in the 1950s long before 257,400 acres in southeast Utah became Canyonlands National Park in 1964. The park was eventually expanded to more than 337,000 acres. Some groups and citizens are now seeking further protection of the land around the park in the form of a proposed Greater Canyonlands National Monument.

The war against tamarisk in the West has taken many forms through the years — cutting, burning and poisoning — but researchers with the U.S. Department of Agriculture finally found something that appears to be making a major difference by visiting the homeland of the plant to bring it to the battle.

Tamarisk leaf beetles were released along the Colorado River in 2004, upstream of Canyonlands National Park. Other releases happened in 2005 and 2006. It didn’t take long before the work of the beetles was evident along the entire stretches of both the Green and Colorado rivers within the park.


story continues below
story continues below

The beetles are still at work — it takes several cycles of infestations to actually kill tamarisk stands — but some wonder if it was necessary and others filed a lawsuit against the Department of Agriculture to re-evaluate the program.

"Some people are looking for a return to the [19th century explorer] John Wesley Powell times. We will never see that. We have these large dams that control the flows and we have manipulated all these different elements," said Steve Young, a longtime backcountry river ranger in Canyonlands. "The system was kind of going into a balance with tamarisk and now we have screwed it up again."

For decades, tamarisk was viewed as a water-sucking, wildfire-enhancing, bank-choking, do-nothing-for-wildlife invader. Federal and state governments continue to spend millions in an effort to control tamarisk.

More recently, researchers are finding tamarisk does have positive impacts on river ecosystems and some wildlife species have figured out how to use it. Birds common to riparian areas often use tamarisk for nesting, including the endangered southwestern willow flycatcher.

The Animal and Plant Health Inspection Service of the Department of Agriculture stopped releasing beetles in response to the 2009 lawsuit brought by the Center for Biological Diversity to protect species like the willow flycatcher, but the cat was already out of the bag, so to speak.

"Given that the beetles are already on the ground this was a less than satisfactory result," said Noah Greenwald, endangered species program director for the Center for Biological Diversity. "We are not fans of tamarisk, but simply removing it with an invasive species only completes half the job because it fails to address the changes in hydrology and habitat that let tamarisk take over in the first place and thus provide no assurance that native riparian vegetation will take tamarisk’s place. This is harmful to the flycatcher and many other species."

Mark Miller, chief of Resource Stewardship and Science over Canyonlands, says the beetles appear to have achieved extensive mortality on some tamarisk stands while others appear less impacted.

The beetles move in, defoliate the tamarisk and move to the next stand. If the tamarisk survives the first wave, the beetles return to do their work again and so on, until the tamarisk dies.

"In areas where tamarisk has been impacted we are seeing a pretty rapid response to take its place from some native vegetation," Miller said. "In many places coyote willow has replaced tamarisk on a one-to-one basis."

The willow, according to a theory, probably would have taken advantage of the unvegetated sand bars left intact by controlled dam regimens. On the downside, there appears to be a number of other non-native plants — like Russian olive thorn trees — primed to jump in and fill the void if tamarisk disappears.

There are other unexpected benefits of the thick tamarisk stands lining the rivers of Canyonlands National Park.

Next Page >


Copyright 2014 The Salt Lake Tribune. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Top Reader Comments Read All Comments Post a Comment
Click here to read all comments   Click here to post a comment


About Reader Comments


Reader comments on sltrib.com are the opinions of the writer, not The Salt Lake Tribune. We will delete comments containing obscenities, personal attacks and inappropriate or offensive remarks. Flagrant or repeat violators will be banned. If you see an objectionable comment, please alert us by clicking the arrow on the upper right side of the comment and selecting "Flag comment as inappropriate". If you've recently registered with Disqus or aren't seeing your comments immediately, you may need to verify your email address. To do so, visit disqus.com/account.
See more about comments here.
Staying Connected
Videos
Jobs
Contests and Promotions
  • Search Obituaries
  • Place an Obituary

  • Search Cars
  • Search Homes
  • Search Jobs
  • Search Marketplace
  • Search Legal Notices

  • Other Services
  • Advertise With Us
  • Subscribe to the Newspaper
  • Login to the Electronic Edition
  • Frequently Asked Questions
  • Contact a newsroom staff member
  • Access the Trib Archives
  • Privacy Policy
  • Missing your paper? Need to place your paper on vacation hold? For this and any other subscription related needs, click here or call 801.204.6100.