Here are a few things to keep in mind when planning a trip to the wilds:
Where to go: The Sierras are crisscrossed with hundreds of trails, most of which are accessible to anyone with spunk and a good pair of boots. Among the most popular are the High Sierra trail, which runs east-west across the crest, and the John Muir trail, which follows a north-south line from Yosemite to Mt. Whitney. For those who want a less rigorous adventure, the National Park Service operates a string of five High Sierra camps, each a few hours' hike apart. The camps offer hot food, showers and beds, but reservations should be made early. There are also a number of beautiful day hikes leaving from Yosemite valley and Sequoia as well as trails on the eastern side of the range.
If you want to feel the rocks under-foot but can't bear to stray too far from the Atlantic, there are plenty of scenic trails throughout the White and Green Mountains. Many of these paths have shelters and tent platforms, and the Appalachian Mountain Club also operates a string of huts along the Appalachian Trail.
When to go: If you're headed west, the general rule is sometime between late June (when the thaw ends) and Labor Day. Although blizzards have occasionally surprised backpackers as early as August, they generally don't occur until sometime in mid-September.
In the Appalachians, the ideal hiking season is somewhat later. If you hold off until August or September you may miss some of the most beautiful Applachian flowers, but you'll also avoid the black flies and insects.
What to take: A pair of good boots are an absolute must--particularly on the granite slab of the High Sierras. Other essentials are a warm sleeping bag, insect repellent, a canteen (don't trust that there'll be water everywhere), and if you're in the East, a light tent and rain poncho (afternoon showers are common, and there is nothing worse than hiking in wet clothes). The cardinal rule, however, is travel light. As an experienced backpacker said, "Put everything you think is absolutely essential in one pile, then take half of that."
Maps and permits: General area maps are available from the forest service, the park service, and the geological survey. Both the Sierra Club and the Appalachian Mountain Club (AMC) also have a good selection of trail maps guides.
Although most trails are open to all, the number of users on some is restricted to reduce ecological damage. Some also require special parking, camping, or fire permits. Get these from the ranger stations in the particular area you want to hike, or from the Sierra Club or the AMC.
Information: For good general information about backpacking (gear, camp preparation, rules of the road), try Walking Softly in the Wilderness (John Hart, $6.95), The Best About Backpacking (Dennis Van Lear, $6.95), or The Climber's Guide to the High Sierra (Steve Roper, $7.95).
For additional information, or information about particular areas and trails, write Sierra Club Headquarters, 530 Bush St., San Francisco, Calif. 94108; or the Appalachian Mountain Club, 5 Joy St. Boston 02108.