Processing of native and exotic leaf litter in two Idaho (U.S.A.) streams

The Russian olive tree (Elaeagnus angustifolia L.) was brought to the western United States from Eurasia during the early to mid-1900s, and has since become a common member of many riparian communities in Idaho. We compared leaf chemistry and in-stream processing of Russian olive leaves (exotic) and various species of native leaves in one hardwater and one relatively softwater Idaho stream. Measurements using air-dried leaves showed that Russian olive contained the greatest concentration of nitrogen, approximately 1.6% of the dry mass, whereas the native species each contained less than 1.0% nitrogen. The C/N ratio of Russian olive was