Hardwood or mixed forest, doesn't have to be a giant undisturbed area. I find larvae all over my neighborhood's wooded trail. You're looking for soft hardwood, but not falling apart. It also doesn't need to be a log because the females don't really seem to tunnel inside to lay eggs, as long as the limb or log is at least a few inches diameter. This time of year I'm finding L1s by rolling over the wood. They're in little soil cavities directly under the wood, or sometimes barely dug into the wood on the bottom surface. Later in the Spring and Summer the larvae will get more active with their chewing so you'll usually see very fine sawdust under the rotting wood. Their tunnels will be close to the surface so they're pretty easy to dig out.
