SISTERS, Ore. -

The Deschutes National Forest said Friday it will apply herbicides to invasive plants next week in an area adjacent to the Metolius River and the Metolius River Trail.

As weather conditions permit during this week, the Sisters Ranger District will use two herbicides (Aquamaster® and Habitat®) to treat invasive non-native ribbongrass and yellow flag iris within a 0.6 acre area next to Gorge Campground on the Metolius River.  The campground closed for the season on September 16th.  

The method of treatment to be used is called “wiping or wicking.”  It involves precise application of herbicide to foliage of target invasive plants to minimize effects to native plants. 

The applied herbicides will dry within an hour of being applied and do not pose a risk to human or animal health under the concentrations being applied. officials said.

The Metolius River Trail will remain open during treatment, but the public should remain on the trail during treatment operations.  Please keep dogs leashed if you are in this area., officials said

Ribbongrass and yellow flag iris are aggressive invasive plants that are overtaking native sedges, wildflowers and shrubs within the river’s riparian habitats.  These invasive plants out-compete most native species and present a major challenge in protecting the unique native vegetation and habitat of the Metolius River.

Restoring and protecting the Metolius Wild and Scenic River and its values including fish, wildlife, water quality, ecology, scenery, and cultural values is a priority of the Deschutes National Forest.  This action, in addition to others, will move that restoration effort forward, officials said.

The two herbicides being used were approved through an environmental analysis in 2005 and a supplemental environmental analysis in 2012. 

Prior to the approval of herbicide use, ribbongrass was experimentally controlled by solarization (covering areas with black plastic for 2 years) and hand pulling.  Any root not completely removed continues to reproduce and neither method is feasible given the size of the infestations. 

For more information, please contact Maret Pajutee at 541-549-7727.