Ecology Distribution Management Info Impact Info References and Links Contacts

General Impact Rubus discolor colonizes areas initially disturbed and then neglected by humans. It then forms large impenetrable thickets of prickly canes with densities reaching 525 canes per square metre. A large quantity of litter develops in mature thickets. The thickets create dense shade, reducing native species diversity and likely limiting mammal movement in gaining access to water. In addition, the tangled mass of thorny stems blocks access of humans, livestock, equipment, and vehicles to pastures and waterways. These dense thickets and litter buildup represent potential fire hazards (Alaska Natural Heritage Program, 2005; and Hoshovsky, 1989). It has the potential to hybridize with native species of Rubus (Oppenheimer pers.comm., 2006). R. discolor is a perennial weed which is difficult to control due to its ability to regenerate from sections of root stock. In forest areas, timber-logging operations create large open areas that are often invaded by R. discolor. When grazed, the thorny stems can injure nasal passages of livestock. Another undesirable aspect of R. discolor is that they are a good source of food and shelter for rats (DiTomaso, 2006; and Hoshovsky, 1989).          Location Specific Impacts: California (United States (USA))   Competition: R. discolor is a pioneer plant that colonizes intertidal zones in California, preventing the establishment of other native plants (Alaska Natural Heritage Program, 2005).