If you're new to trail running, check out this trail running 101. Here's a list of seven "must knows" before you head for the trails.
An Introduction to Powerhiking – iRunFar
Trail Running 101, the Trail Runner's Checklist
Member of the Month - San Francisco Road Runners Club
Trail Running 101 BLISTER Outdoor Media & Gear Reviews
Trail Runner's Checklist
Trail Running 101 BLISTER Outdoor Media & Gear Reviews
How Runners Can Support the Environment for Earth Day - Xero Shoes
Kim Levinsky and Sassquad Trail Running – iRunFar
The Ultimate Trail Running Checklist
Trail-Running Checklists
Trail Running For Beginners: How To Start Trail Running