The sand dunes of the Pacific Northwest are dynamic and house diverse dune mat communities. Introduction of non native species into dune mat communities change soil characteristics of dunes, such as the case of yellow bush lupine (Lupinus arboreus). Lupine establishment provides ideal conditions for other non natives to invade. These impacts have been observed within the Lanphere Dunes Unit of the Humboldt Bay Wildlife Refuge in Arcata, California. The United States Fish and Wildlife Service (USFWS) plans to test lupine eradication methods in a one acre parcel within Lanphere. This study aims to collect baseline data for that parcel, focusing on the effects of lupine on native dune mat. We determined the number of lupine individuals within the site, the species composition compared to two reference sites, and soil organic matter content within the project area. The large amount of lupine was correlated with the high cover of annual grasses. In contrast, the uninvaded area had the highest cover of dune mat and open sand, representing a healthy dune ecosystem. Soil samples showed that the non native species contributed to the increased organic matter content within the soil. This study provides insight into the impacts of lupine on a dune community.
Environmental Science and Management