Los Penasquitos Canyon - East Approach
Distance: 6.4 miles round trip to falls, Out-and-back
Hiking Time: 3 hours (round trip)
Elevation Gain/Loss: 300'/300'
Tail Use: Mountain biking, dogs allowed
Directions: Exit Interstate 15 at Scripps Poway Parkway/Mercy Road. Go west on Mercy Road for 1 mile to a T-intersection with Black Mountain Road. Straight across, to the west, is your starting point, the eastern staging area for Los Penasquitos Canyon Preserve.
Description: Take along a picnic lunch and a blanket on this hike. There are many fine places-sunny meadow, oak-shaded flats, and the sycamore-fringed stream side-to stop for an hour's relaxation. A good turnaround point is a small set of waterfalls and pools in the canyon bottom. This is about 3 miles out, midway through the Los Penasquitos preserve.
From the large staging area, set off on the wide trail to the west. In the first mile, it hugs Los Penasquitos Canyon's south wall, a steep, chaparral-covered hillside (los penasquitos means "the little cliffs").
As you pass near the Johnson-Taylor Ranch (screened from view by willows and dense vegetation along the creek), you'll notice several nonnative plants-eucalyptus and palms, for example-introduced into this area over the past century. Nest you enter a long and beautiful canopy of intertwined live oaks, accompanied by a lush understory of mostly poison oak.
Mile posts along the roadside help you gauge your progress. At mile 2, the trail winds out of the dense cover of oaks and continues through grassland dotted with a few small elderberry trees. Wildflowers such as wild radish, mustard, California poppies, and bush mallow, and violets put on quite a show here in March and April. Look, too, for the fuchsia-slowered gooseberry, quite unmistakable when in bloom.
Along the way to the falls, there are two creek crossings to the north leading to a parallel trail on the far side of the creek. You could follow that trail when you return from the falls, but it is not as scenic as the main south-side trail.
At the 3-mile marker, the road winds up onto a chaparral slope in order to detour a narrow, rocky section of the canyon. Near the top there's a wide spot, with racks for securing bikes, and a foot trial descending north to the falls area, constriction in the the bedrock. At time voluminous cascade of water tumbles through here. Polished rock 10 feet up on either side testifies to its maximum depth. By fall, the follow slow to a trickily, and the pools and potholes int he bedrock may be filled with stagnant, odiferous water. The outcroppings of greenish-gray rock, just in this one small area, are a type called Santiago Peak volcanics; they're typical of the metavolcanic rock on Santiago Peak in the Santa Ana Mountains. You can retrace your steps from here.
Description from: A Foot & Field San Diego County: A Comprehensive Hiking Guide, 2011