(8:41 minute video segment , PBS Oregon Field Guide, Season 21, Episode 2111 ) Take a look at some of the Willamette Valley’s savannah-prairie lands. See how the savannah has changed due to lack of fire. The oak savannah, one of the rarest and quickly diminishing of habitats is being crowded out by plants normally held at bay by fires. See how lack of this habitat impacts the survival of wildlife. But some land managers are working to restore pockets of the once-common oak