Are the trails where you ride in danger of being developed? Consider forming a trail-preservation club with your riding buddies. Having an official name, website, and an army of help can facilitate a dialogue with your local government authorities about sponsoring and maintaining the trails you frequent.
Post fliers for an initial club meeting at your favorite trailheads and/or in your area's tack and feed stores, with the owners' permission. Send meeting dates and times to your regional horse publication for its community-events section. You'll find out just how many people are using the trails you'd like to save.
After you've assembled a core group, find out how you can help conserve trails by contacting your state's horse council, your county extension office, and the Equestrian Land Conservation Resource (815/858-3501; www.elcr.org).