What snapped that tree? Everybody is asking this and similar questions, obsessed as we are as a culture with forensic investigation. Was it weevils gnawing from within? Was it wind or snow load that toppled it? Or did it die for some other reason and snap due to lack of internal structural integrity?
Read Tom Wessels' wonderful little book and learn. Better, pop it in your backpack and learn as you hike. Although written for forests of the northeastern part of the U.S., the principles involved are pretty much the same in all forest. (The particulars surely do vary by bioregion, though.)
With dozens of color photos and clear, concise writing, it’s hard to go wrong with this book if you’re interested in forested landscapes. For instance, Wessels’ chapter on how to tell if a forest has overgrown an agricultural field is full of cool details that are widely applicable. Part of this has to do with the fact that - at least in North America - farmers have cleared and abandoned fields in pretty much the same way for hundreds of years.
Read the signs like a real detective and appreciate your forest walks even more with this handy guide from ecologist and environmental biologist Wessels.