Stebbins Cold Canyon Reserve, part of the University of California Natural Reserve System, is one of the few UC reserves that allows public access. Plant and animal communities in these 640 acres are largely intact and hold a healthy number of species. The Blue Ridge Loop hike is best in spring and fall, as the area is subject to mudslides in winter and heat in summer.
Trail Notes: Just inside the gate the trail forks to the left for Pleasants Ridge Trail. Stay right. Look for small trail signs starting with the number 01 after you pass the gate. The Homestead Trail stays on the east side of Cold Creek for the first 1/2 mile. Quickly you come to an eastern tributary. Although its watershed is small, the floodwaters of 1995 raised havoc here. Most of the riparian vegetation in the creek below was stripped away along with a great deal of soil that, combined with the raging waters, nearly took out the highway, too. Since then tons of debris have been removed from the trail, and the streambed is rebounding with plant life. You may see shooting stars and the shocking magenta flowers of redbud around March and April. To the right is the Blue Ridge Loop trail junction.
At 1/5 mile you enter the Reserve proper and pass through a new gate to a new display case packed with great information. Staff at the UC Reserve system is very active here at Stebbins, leading guided hikes and training hike leaders. It is an active ecological study area for students and teachers at UC Davis. Please leave study areas undisturbed. Pass a tall, classic-looking gray pine (Pinus sabiniana), and then the trail negotiates a short hill with sturdy water bars. At 1/3 mile you cross over another small hillock that came down as a land slump with many plants intact. In February, shiny brown seeds of the buckeye litter the ground, sending out pale white roots. All along the trail later in spring are wildflowers like brodiaea, monkeyflower, Indian paintbrush, white flowered yarrow and yerba santa, western wallflower, and golden fairy lantern. To the west is a prominent rocky peak on Blue Ridge that often hosts hawks circling overhead, and its sheltered ledges are ideal nesting sites for the turkey vulture.
Before the crossing of Cold Creek, look for a side trail to the right marked by a scrub oak. The creek here is a good place to see the Pacific tree frogs or yellow-legged frogs whose calls you may have been hearing. A large boulder at trail’s end has a rounded hole or mortar made by Patwin Native Americans for grinding acorns to flour. Back on the main trail at 1/2 mile you come to Cold Creek. If it is moderately high you may find a dry rock-hop crossing fifty feet upstream on the left, or enjoy the plunge on a warm day. Start the ascent to the homestead now and at 3/4 mile cross over a serpentine spring on a miniature wooden bridge.
The trail climbs steadily above the creek through dense chaparral species like ceanothus and mountain mahogany (Cercocarpus). The trail veers south to follow what looks like a tributary of Cold Creek, but a glance at the map shows you are still on Cold Creek. What I believe is going on is a nomenclature anomaly. The larger Wild Horse Creek, which joins Cold Creek below, has been given tributary status by mistake. According to standards set by the Geographic Board, the waters running into Putah Creek should be called Wild Horse Creek. But local usage and custom are strong, and to correct it would only cause further confusion.
Walk steeply through a brushy section that can be a virtual tunnel if left unpruned. On my hike the tunnel was cleared back and regularly spaced water bars installed to prevent erosion. Just beyond, a sign stating “no entry please” requests hikers to stay off a fragile hillside. On these soils even a small informal trail can lead to a major landslide. Soon, on the left side of the trail is the Vlahos homestead near some meadow (probably cleared for goat grazing) and an enormous, many-branched gray pine. All that’s left of the home is a low stone wall, an old well, and some rusted junk.
At 1-1/4 miles is the turnoff for the loop hike. But first, don’t miss the cold house that has given Cold Creek its name. Continue by crossing a small tributary, go down and cross Cold Creek to see the slightly better-preserved stone walls of the cold storage building used by Vlahos to store his goat cheese. Big oaks, maples, and bays make sure this delightful place is always cool and shady. You may follow the creek a short distance to a waterfall and pool for wading or observing aquatic life.
Return to the loop trail junction, unsigned at the time this hike description was written, marked by a hunk of rusted metal rife with holes like it was Swiss cheese. Head up and left through oak and bay forest following old galvanized pipe. Go through some chaparral undergrowth then return to the creek. You will climb a few railroad tie steps then return to creekside again at 1-1/2 miles. Now begin a short but strenuous section of trail gaining 800 feet in 1/4 mile. It’s a real quad burner but just pretend you’re on your Stairmaster with the bonus of better air quality and views. The trial will employ both short switchbacks and 176 high steps between here and the ridgetop. At 1-3/4 miles step out of a chamise thicket into the open for great views of Pleasants Ridge. The trail splits at an unmarked junction. Take the right fork and soon splendid views emerge to the west of Lake Berryessa, Cedar Roughs, Mount St. Helena, Cobb Mountain, and Mount Konocti. Pass a high-maintenance chaparral section, then around mile 2 you will see the first of several perfect sandstone outcroppings ideal for a break for lunch. As the trail rises and falls on the ridgetop over various peaklets, look east through the gap of Devil’s Gate and see on a clear winter or spring day not only the city of Davis but a snow-covered Sierra Nevada, with Mount Lassen to the north.
Around 2-1/4 miles I found myself in a seeming dead end. If this happens to you, back up a bit and look for a sandstone slot to shinny up. Distant Snow Mountain and Goat Mountain come into view as you negotiate interesting passages over rock interspersed with bits of trail. Soon the homestead will be directly below. At 2-1/2 miles look directly along Blue Ridge to Berryessa Peak, then descend another peaklet. The trail will become distinctly easier now, the former high point of the old trail. Watch for the trail tread to totally disappear as it takes a sharp left turn over a sandstone ledge. The ridgetop is a great place to observe raptors close up. At a low point in the ridge, they will come sweeping just above the tops of the chaparral as they cross from one canyon to the next.
At mile 3 the trail charges bravely up a steep crumbly ridge, tops out, and turns briefly toward the lake side of the ridge. For photographers, look for another massive sandstone slab that provides foreground interest for a lake shot. Hang a right and you’re on the east side again. A series of long switchbacks avoids a former environmentally destructive gully trail. Beyond 3-1/4 miles an unmarked side trial leads to a don’t-miss dramatic overlook of the lake, Devil’s Gate, and Monticello Dam. Watch your footing extremely carefully here due to loose rock and big drop-offs.
Get back on the main trail and enjoy the last mile. It’s easy going on the new switchbacks, sometimes over industrial size water bars placed here to minimize erosion on this highly erodable slope. About the time you hear the creek again at 4-1/2 miles, the trail splits. You can take the left fork on the fire road back to the highway, covered in landslide debris for years but now cleaned up, or the right fork heading down to the creek then up to the beginning of the loop.
From: Great Day Hikes in and Around Napa Valley, by Ken Stanton, Bored Feet Press, 2008