Invasive weed management

Klamath Wilderness Inventory Project

Klamath Wilderness Inventory group at wilderness border.

The Mid Klamath Watershed Council (MKWC) was supported by the National Forest Foundation in 2010 to perform noxious weed inventory in the Klamath wilderness areas, including the Marble Mountain Wilderness and the Siskiyou Wilderness.

Inventory and Monitoring is important in these remote wilderness areas as invasive weeds can grow into sizeable populations if left undetected. Late detection significantly increases eradication costs and allows for increased damage to habitat functioning. There has not been an extensive effort to inventory invasive weed populations in the Marble Mountain and Siskiyou Wilderness Areas. The Marble Mountains are of particular concern for invasive weed infestation as there is a high level of cattle grazing and horse packing that occurs within in its boundaries. These activities are known to spread invasive weeds. Both wilderness areas are also at a higher risk due to the abundance of wildfire occurrence and fire suppression efforts in 2008.

Lucius Robbi pulls a bull thistle in the Marble Mountains.

We worked closely with Forest Service managers from the Klamath National Forest in the spring of 2010 to prioritize trails for inventory.  Prioritization was given to highly disturbed trails and areas, primarily from recent wildfires, and also to high use areas.

The inventory took place between June 26^th and August 29^th 2010 in both the Marble Mountain and Siskiyou Wildernesses.  Participants included MKWC’s three youth stewardship interns, two AmeriCorps Watershed Stewards Project members, the Klamath-Siskiyou Outdoor School (25 students) as well as project directors.  We covered over 100 trail miles and mapped out 25 weeds sites.  Weed species mapped include: St. John’s Wort (Hypericum perforatum), Mullein (Verbascus thapsus), Himalayan Blackberry (Rubus armeniacus), Bull thistle (Cirsium vulgare), Prickly lettuce (Lactuca serriola) and Mallow (Malva neglecta).  Out of all these weedy species, St. John’s Wort is the only rated weed, C-rated.  Sites mapped that were most concerning were found within intensely burned areas because, as expected, any weedy species within such a disturbed area were showing rapid expansion.  These sites included the Himalayan blackberry and the mallow sites.

Himalayan blackberry discovered in an intensely burned area near One-Mile Lake.

The involvement of our three Youth Stewardship interns was integral to the success of the Klamath Wilderness Inventory Project.  This was the first year that MKWC hosted youth interns, they were involved in all five wilderness inventory trips.  Since we were already out in the wilderness, doing plant surveys, we took the opportunity to partner with the California Native Plant Society's Rare Plant Treasure Hunt.  While searching for invasive plant species, we were able to check on previously mapped rare plant locations as well as identify 18 new sites unmapped by the California Native Plant Society.  The rare plants mapped are species endemic to the unique Klamath-Siskiyou bioregion including the Klamath Gentian (Gentiana plurisitosa), Grouse whortleberry (Vaccinium scoparius) and English Peak Greenbriar (Smilax jamesii). 

Youth Stewardship Interns are trained to use GPS to inventory invasive plants.

The combined participation in the weeds inventory and the rare plant treasure hunt was a fantastic learning experience for all involved; AmeriCorps volunteers, youth interns and staff members.  The weeds inventory project was enhanced by the opportunity to also search for some of the rare plants that make the Mid-Klamath so unique, demonstrating  some of the reasons that we manage invasive plant species.

Top photo: Sunset at Clear Lake, Marble Mountain Wilderness.  Photo taken by Jillienne Bishop.