Herbivore Avoidance of a Simple Digitalis Extract

Browsing or clipping of seedlings by herbivores hinders reforestation efforts in the Pacific Northwest. Plants that are naturally avoided by herbivores may provide a source of aversive agents to serve as repellents. This study was conducted to determine whether mountain beaver (Aplodontia rufa) would ingest apple cubes treated with a simple water extract of digitalis (Digitalis purpurea). Responses mere assessed in two-choice and one-choice tests. Under both test regimes, mountain beavers reduced (P < 0.05) their intake of apple treated with the extract. It was concluded that digitalis may be an effective source of aversive agents to deter herbivore damage in the Pacific Northwest.