La Costa Valley and La Costa Glen are Carlsbad City trails that are near each other and relatively short. They are within or in close proximity to similar riparian and coastal chaparral/sage scrub habitats, but the trails do not directly connect.
The trip described here assumes the goal is to do both trails in an expeditious manner and presents a simple way to accomplish this. The La Costa Valley Trail begins on Paseo Aliso and continues along a well-maintained, decomposed granite path for 0.5 mile to Avenida Helecho. The trail is about 50 feet above a broad wetland but immediately below the backyards of homes that line the north side of the path.
This provides a stark contrast between these semi-wild lands that are the remnants of coastal San Diego’s native flora and exotically landscaped, suburban habitat that has replaced most of it.
As you walk along the path, notice numerous native shrubs along the south (right) side of the trail. Prominent among these are toyon (Heteromeles arbutifolia), with its bright red berries in the fall, California buckwheat (Eriogonum fasciculatum) in bloom nearly throughout the year, lemonadeberry (Rhus integrifolia), coast prickly pear (Opuntia littoralis), and laurel sumac (Malosma laurina). The public is prohibited from entering the wetlands below, and observing them from the distance of the trail makes it hard to identify most of the species living there. However, southern cattails (Typha domingensis) are likely to be prominent in the wettest areas and white plumes of the invasive, nonnative pampas grass (Cotaderia jubata) are easy to spot from this distance.
The Carlsbad City Trail ends when you reach Avenida Helecho. A similar trail continues on the other side of this street, but it is owned and maintained by a local homeowners’ association and has a prominent sign stating that it is for the use of La Costa Valley residents only and that trespassers will be prosecuted. Instead of wandering up this illegal option, stay to the west side of Avenida Helecho, turn right, and walk about 200 feet to the La Costa Valley South Trailhead. Follow this paved trail west and then south for 0.3 mile to Calle Barcelona. It passes through a similar suburban-wild land interface, but with more riparian species thriving beside the trail. These include a number of large trees: sycamore, coast live oak, cottonwood, and black willow, as well as smaller coastal scrub species, such as coyote bush (Baccharis pilularis), coastal sagebrush (Artemisia californica), California sunflower (Encelia californica), and San Diego sunflower (Bahiopsis laciniata). Upon reaching Calle Barcelona, turn right and continue west on the paved roadside path for 0.7 mile to the La Costa Glen–Calle Barcelona Trailhead.
The La Costa Glen Trail takes you north about a mile, from Calle Barcelona to La Costa Avenue, giving you a nearly 2-mile out-and-back addition to your adventure. The trail is a broad decomposed-granite path that parallels Encinitas Creek as it flows toward Batiquitos Lagoon. There is a large retirement community along most of the west side of the trail. However, there is enough of a buffer between the retirement village and the trail to have allowed for a dense growth of native chaparral and coastal sage shrubs to complement those on the east side of the trail.
In addition to the species mentioned above, expect to find black sage (Salvia mellifera), California buckwheat, coastal bushmallow (Malcothamnus fasciculatus), goldenbush (Isocoma menziesii), and the San Diego wreath plant (Stephanomeria diegensis). These species bloom at different times of the year. Visits in the spring and early summer are rewarded with brilliant displays of lavender bushmallow blooms, while in late summer and fall the bright yellow of goldenbush inflorescences will dominate the trail. Even late fall and early winter provides a show with the three different Baccharis species found here looking as though they are covered with snow as a result of their small but abundant white flowers.
To extend the walk, continue down an unpaved trail to Leucadia Boulevard before returning to your vehicle.
La Costa Valley and La Costa Glen trails
Distance from downtown San Diego: 30 miles (Carlsbad). Allow 40 minutes driving time. From I-5N turn right (east) onto Leucadia Boulevard in Encinitas and drive to Garden View Road. Turn left (north) onto Garden View Road. It will become Calle Barcelona as it bends toward the east. Turn right at the first signal into the Forum Shopping Center. Park in the northeast corner of the parking lot, then walk east on Calle Barcelona, crossing at El Camino Real. Then take an immediate right (east) to Paseo Aliso. Go left (north) onto Paseo Aliso to the signed La Costa Valley Trailhead to start the first trail for a total of 0.5 mile.
Hiking length: 4.15 miles.
Difficulty: Easy with minimal elevation gain/loss. Bicycles and leashed dogs are allowed.