Newly listed noxious weed 'Phragmites Australis' goes by several common names

Steve Edwards

BCJ News

Readers may never have heard of Phragmites Australis and even more likely never seen it. But, it's in Blaine and Hill County, and that's not good. Also known as 'common reed' or 'giant reed,' the aquatic invasive species was added to Montana's noxious weed list in 2015. Blaine County Weed Coordinator Christian Lehnart said, "Phragmites (said frag-my'-teez) is very tough to eradicate because it's a grass and usually in a place that's wet and hard to access."

Weed experts at Montana State University say the key to eradicating Phragmites is correctly identifying it. Although not common along the Hi-Line at this time, exotic Phragmites is found world-wide and in every part of the continental United States. Unfortunately, the 'bad' Phragmites imitates a native Phragmite in appearance and prefers the same type of habitat. In Montana Phragmites is a 'priority 1A' plant meaning the plants are present in the state but have a limited presence. There is hope to eradicate the known patches and stop the spread of the noxious weed.

Lehnart said he is aware of three separate patches in Blaine County. The most easily visible is north of the railroad tracks along Highway 2, in the area near the Lohman raceway. At this writing that patch is brown, from last year's dead growth. Lehnart explained, "The new growth is coming on below the dead parts. Our challenge will be to access the area, remove the dead growth and then spray to stop new growth." Sometimes the old growth can be burned, other times it can be mowed. The problem often is that the plants like a wet area, grow in very thick formations and make access to spray challenging.

Lehnart said there are two other identified patches in Blaine County, one is further west on Highway 2 and north of the railroad near the property now called "Hansen's Family Campground" or "the old KOA." A third patch is east of Chinook, again along Highway 2 and near the railroad. Because the exotic variety mimics the native Phragmites, the BLM had a sample genetically tested from the patch near Lohman to assure it really was the invasive species.

There are several reasons why exotic Phragmites need to be stopped. The plants grow in such thick concentrations that they often block access to water for wildlife and, possibly, domestic livestock. The exotic variety also produces a lot of dead material which can be additional fuel for wildfires. And in ditches along roadways, the plants, sometimes growing to 20 feet in height, can be a traffic hazard because they block operators' sightlines.

Experts say the best prevention for Phragmites is to leave natural vegetation undisturbed around wet areas wetlands. The plant needs bare ground to get a start and vigorous plant varieties around wetlands act as barriers to the invasive species. With plants already in the county, precautions are recommended to stop the spread of Phragmites.

County Extension Agent Ben Hauptman has examples of the plant in his office at the courthouse annex and can provide information to help identify whether a Phragmites-type plant is exotic or native. Online there are several good sources for information. See http://mtweed.org/wp-content/uploads/Phragmites-ID.pdf. The site has helpful photos, especially for determining if plants are native or exotic. Another helpful online publication, by Montana State University Extension, is http://mtweed.org/wp-content/uploads/MSU-Publication_Watch-Out-for-Phragmites.pdf. Call Blaine County Weed Control, at 357-2340, to report suspected Phragmites along state highways or country roads.