Ecologists increasingly view disturbances as a natural part of the forest landscape. However, anthropogenic disturbances, brought about either by introduced species or forest management, may not mimic natural disturbances. Understanding the multi-trophic and multi-scale effects of anthropogenic disturbances is the first step in mitigating their negative effects. I studied forest disturbance in two different ecosystems in California: oak woodlands in the San Francisco Bay Area and mixed conifer forests in the Sierra Nevadas. The types of disturbance studied in each of these systems are very different. In the Bay Area, I examine an invasive forest pathogen, while in the Sierras I study fire and forestry practices. However, that these studies can be viewed through a common lens of how habitat disturbance can have many multi-scale and multi-trophic level effects, despite the fact the the ecosystems and fauna studied are very different.