Scratch and sniff pungent bay leaves at Pepperwood Spring, near McCain Valley in East County.

Tucked into the fresh-scented folds of a high-desert canyon north of Interstate 8, Pepperwood Spring begins as a network of tiny rivulets issuing from damp pockets of sand. The rivulets conjoin, gather force, and divide again into several streams trickling through a darkened, three-dimensional maze of heaped boulders. Emerging into light, the separate strands meld again. The reunited stream of water halfheartedly cascades over rounded boulders, spreads thin, and finally sinks from sight into porous sand.

The area around Pepperwood Spring is dotted with scores of fragrant pepperwood (a.k.a. California bay) trees. These small trees are commonplace in the coast ranges of central and Northern California, and they exist in isolated colonies surrounding certain springs and streams in San Diego County. When crushed and sniffed, pepperwood leaves give off an odor that is pleasant but, if overdone, the cause of a headache. Pepperwood Spring is also remarkable for its extreme isolation. No sign of civilization can be seen amid the boulder-studded canyon walls surrounding it. Mountain lion and coyote tracks in the sandy soil outnumber those of rubber-soled humans.

The eight-mile round-trip hike to and from Pepperwood Spring starts from Cottonwood Campground, in the Bureau of Land Management's McCain Valley area. Take along a compass, if only to maintain your general course north across the boulder-strewn landscape.

To get to McCain Valley from San Diego, follow Interstate 8 east for about one hour to the Boulevard exit. Go right toward the community of Boulevard, then head left (east) on Old Highway 80. Go 2 miles to McCain Valley Road, then follow it 12.7 miles north to Cottonwood Campground. The trail begins at a small parking turnout near Cottonwood Campground's far east end.

Follow the obviously trodden trail, at first east then generally north. The trail is marked intermittently by barely legible or illegible signs. Be sure to avoid taking any side trails that branch either east or west. At about 3.3 miles from the start, the trail bends northwest and starts descending into the canyon containing Pepperwood Spring. Before long, the now-obscure trail passes through a heavily eroded area, curves north, and starts dropping in earnest through shrublike pepperwoods and clumpy chaparral vegetation. From the foot of the trail, some 4 miles from Cottonwood Campground, the boulder maze mentioned above can be found a short way up the little stream cascading over the rocks.

If you visit Pepperwood Spring this year, do so soon. It could run dry before long.