Invasive Plant Species Report 2016

Burkman, Peggy; Gutt, Matthew

Apostle Islands National Lakeshore was monitored and treated for invasive species during the 2016 summer and early fall seasons. The mainland and 14 of the 21 islands were monitored and/or treated this year. Areas of primary interests (trails, historic landscapes, and easily accessible beaches etc.) which consisted of high human use by tourists, maintenance crews, or contractors. Previously monitored locations were later treated by hand, mechanically, or chemically. Species of high priority concern included tansy (Tanacetum vulgare), Canada thistle (Cirsium arvense), bull thistle (Cirsium vulgare), spotted knapweed (Centaurea stoebe) , purple loosestrife (Lythrum salicaria), glossy buckthorn (Rhamnus cathartica), and vinca (Vinca minor). Although these species were managed during the 2016 season, further yearly monitoring is needed to insure continued suppression of these invasive species.