About a year ago I found a picture posted online showing a beautiful view of the Pacific coastline along San Mateo County, viewed from the Irish Ridge Trail. I immediately resolved to hike there on a day that would be clear of the typical coastal marine layer (aka fog) that often sits just off the coast along the Peninsula south of San Francisco.
After a bit of research I determined that the Irish Ridge Trail is located in Purisima Creek Redwoods Open Space Preserve, one of 26 parks managed by the Midpeninsula Regional Open Space District. I had previously hiked two sections of the Bay Area Ridge Trail in the Open Space Preserve without finding this particular trail. It turns out that it is in the southwestern part of the preserve, connected only by a couple of trails to the Purisima Creek Canyon in the heart of the preserve. The most immediate access is via a trailhead located on Tunitas Creek Rd about 2½ miles west of Skyline Blvd, CA-35.
Recently I selected a day that I thought would be fog-free and went for a Fall afternoon hike in the redwoods. Purisima Creek Redwoods is one of my favorite open spaces on the peninsula. It was a lovely hike, mostly through forest, with a teaser viewpoint and then a big, open viewpoint.
I explored all of the trails in the southwest section of the park in a 7½ mile out-and-back hike with 1600 vertical feet. The orange dot on the GPS track shows the trailhead on Tunitas Creek Rd. After hiking 0.3 mile on the Grabtown Gulch Trail you go left on the Borden Hatch Mill Trail for 0.2 mile and hike the length of hikers-only Bald Knob Trail to reach the Irish Ridge Trail. Near the far end of Irish Ridge Trail is Lobitos Creek Trail, which I explored all the way to an End of Trail sign.
Bald Knob Trail kind of skims along the side of Bald Knob, climbing to the highest point of the hike. Irish Ridge Trail then descends 600 feet to Lobitos Creek Trail, which descends another 300 feet. Since the outbound hike is predominantly downhill, the return is primarily uphill. The average grade on Irish Ridge and Lobitos Creek Trails is nearly 10% but it really felt like a pleasant slope.
From the very beginning of the hike – in fact, from the drive down Tunitas Creek Rd – I knew I would be enjoying a redwood forest environment. I don’t think I ever get tired of hiking in redwood forests! Redwoods are one of the oldest trees in the world as well as the tallest, growing up to 360 feet tall. Most of the old-growth redwoods on the peninsula were logged over a century ago, so the present trees are mostly second growth, “only” 100 years old or so.
Redwoods grow in the moist environment of California’s Coastal Range, encouraged by Pacific storms and by the never-far-away marine layer that often drapes the hills in fog. Ferns also thrive in this environment, and there were many lush ferns along the trail.
Rock walls next to the trail, as well as down logs, were covered in feathery moss. Some of the moss looked like it could blow around in a breeze.
In addition to redwoods, the forest contains madrone, Douglas fir, and tanoak with varied and interesting shapes in the shady forest. I think this tree, with a growth pattern that emphasizes the slope of the hillside on Bald Knob Trail, is a madrone.
Near the junction between the Bald Knob and Irish Ridge Trails there was a small grove of skinnier trees, perhaps tanoaks.
Along Bald Knob Trail there were a couple of places with what I think of as teaser views: barely enough space between the trees to see that there should be a view. I think that the ridge I could see at the teaser views is Durham Ridge. In any case, the more open viewpoint I mentioned previously was on Irish Ridge Trail, and you certainly know when you get there! Suddenly the trail passes through a clearing in the trees, big enough to open up a fantastic view to the southwest. A bit more to the south you can see row upon row of the lower-elevation hills at the western edge of the Santa Cruz Mountains.
The sun reflected brightly from the surface of the Pacific Ocean. While the famed marine layer was somewhat off-shore, there was enough haze to blur the horizon.
As the Irish Ridge Trail returned to forest, I started to see a few wildflowers. I was really surprised to be seeing wildflowers in bloom in November! Looking casually, these looked like common dandelions (Taraxacum officinale) but I think they are actually false dandelions or mountain dandelions (Agoseris heterophylla or Agoseris hirsuta), members of the agoseris genus, even though the blooming periods for these two species are supposed to end during the summer.
After hiking to the end of the Irish Ridge Trail I returned a short distance and turned onto the Lobitos Creek Trail. According to the preserve trail map, this trail is not maintained. Indeed, there was more forest debris on the trail, and in one place it looked more like a rarely-used car track, with two tire paths and grass and other plants growing between. I came across what looks like a past-prime common self-heal (Prunella vulgaris).
Next to the trail I noticed some other plants with tall leaves resembling iris. A few of the dead leaves had formed into curls reminiscent of ribbon, making interesting patterns.
After I reached an End of Trail sign on Lobitos Creek Trail I returned to the trailhead. It had been a lovely walk through a mostly redwood forest with a beautiful view of the Pacific Ocean, on a warm and pleasant Fall afternoon.