Friends Group members are victorious after removing every flowering white sweetclover plant at river crossings between the Kanuti River and Coldfoot. June 2008. FWS photo.

A Friend pauses from pulling weeds to move road flags as the group progresses, helping assure their safety. June 2008. FWS photo.

At its nearest point, the Kanuti Refuge lies just eight miles west of the Dalton Highway, the road that leads from Fairbanks north to Prudhoe Bay. At least six Koyukuk River tributaries cross the highway and later enter the Refuge. Kanuti Refuge staff and our cooperators are increasingly concerned that these waterways (especially Jim River, Fish Creek, Prospect Creek, and Bonanza Creek) could become routes for dispersal of invasive white sweetclover (Melilotus alba) into the refuge. This non-native plant readily invades open and disturbed areas and has become established in extensive areas along many roadsides and even some river gravel bars in interior, south-central and southeast Alaska. White sweetclover has rapidly colonized the Dalton Highway corridor near the Refuge, moving 120 miles northward between 2000 and 2007.

Since 2006, The Friends of National Wildlife Refuges (Friends) have cooperated annually with Kanuti Refuge, the Bureau of Land Management (BLM), the National Park Service, Alaska Department of Transportation, Alyeska Pipeline Service Company and others to control white sweetclover at key sites where it could easily disperse into the refuge. To the best of our knowledge, the Refuge currently is free of highly invasive non-native plants. To date, control efforts have focused primarily on manual pulling. This year crews of volunteer weed warriors continued removing plants manually, but expanded the effort to include using weed trimmers, with the goal of eliminating 2008 seed production. The expanded effort required that infested areas be visited twice during the growing season in June and July. The first effort was undertaken earlier than in previous years, to better target seedlings. By late July, two crews of 13 Friends members and agency staff successfully achieved their goal – removing all outlying flowering plants at river crossings between the Kanuti River and Coldfoot.

As a result of these annual weed pulling events, white sweetclover infestations have been reduced at the target sites along the Dalton Highway. In addition, refuge staff conducted surveys along rivers downstream of the highway and within Kanuti Refuge. They report that the plant had not spread down drainages and into the Refuge.  The war against invasive white sweetclover is not over; these dedicated partners plan to continue pulling the weed at river crossings annually to prevent its spread. Knowing that their labors are paying off is providing incentive and new enthusiasm to the effort to keep sweetclover out of pristine refuge lands.

This year BLM also started developing a formal weed management plan for the Dalton Management area, holding public meetings in communities that will be affected if white sweetclover colonizes habitat in their area. It is hoped that this plan will incorporate a large-scale integrated approach that may include potential use of herbicides and other methods for controlling non-native, invasive plants.