• Blue Sky Ecological Reserve
  • Blue Sky Ecological Reserve
  • Blue Sky Ecological Reserve
  • Blue Sky Ecological Reserve


2 miles, out-and-back





Blue Sky Ecological Reserve

About this trail

This hike demonstrates why San Diego is a biodiversity bonanza. The rolling hills in and around Poway create a unique mix of habitat types and climatic conditions. These varied ecosystems foster an incredible amount of plant and animal diversity. Get to know several of these habitat types through a comfortable and accessible walking tour through Blue Sky Ecological Reserve.

A largely flat gravel and dirt path departs from the parking lot on Espola Road, first dropping into an oak canyon/riparian corridor. This part of the trail is mostly shaded, thanks in large part to the stream on the north side of the trail that provides enough water for relatively tall coast live oaks and western sycamores to thrive. Go left onto the Oak Canyon Trail to descend into a cool and refreshing oak grotto, where these beautiful trees and a wide section of the stream can be explored up close, but watch out for poison-oak.

Upon exiting the oak grotto, the trail continues to follow through the oak woodland above the stream until a fork is reached just under 1 mile from the parking lot. One branch continues parallel to the stream (stay left at the fork), eventually reaching the Ramona Dam after an additional 1.5 miles. There is a small outdoor classroom for educational programs and a pit toilet on the right side of this trail, just after the fork. A right turn at the fork will lead to the Lake Poway Dam in a little over 1 mile. For further distance and/or challenge, a number of additional trails can be reached from here including the Lake Poway Loop and the Mount Woodson Trail.

Whether you choose to turn back at the fork or explore one or all of the trail extensions, be sure to find a break in the shelter of the oaks lining the trail to catch the view of the surrounding rocky hills covered with coastal sage scrub, a habitat characterized by aromatic, drought-resistant plants. Now try to gain a little elevation to view another habitat—the cool, shaded corridor you walked through from the parking lot. The importance of water and gravity becomes abundantly clear when the green “vein” of oaks is seen snaking along the valley floor below much drier hillsides.

We’ve rated the difficulty for this hike easy, with minimal elevation gain. Before you go, check to ensure the trail is open. More detailed information about the area can be found at Blue Sky Ecological Reserve. Bicycles are not allowed.

What you’ll see

This gorgeous reserve is one of 119 owned and managed by the California Department of Fish and Wildlife for habitat conservation, but it is the only one with a full-time naturalist. The naturalist, along with volunteer docents, lead programs to educate the public about the plants and animals living here. During the weekends, there are free docent-led walks. See their website for details. The 700-acre reserve provides a perfect opportunity to experience and learn about the natural surroundings first-hand.

Keep an ear out for calling frogs as you near the cool water, and look for birds, one of which is the yellow-rumped warbler (Setophaga coronata), one of the county’s most widespread winter visitors, found in most habitats. It is the only warbler in the county with a distinct yellow patch on its rump. Otherwise, the plumage varies greatly by the bird’s age, sex, and season. Through the winter, the birds are dull brownish or grayish, softly streaked darker, with some degree of yellow on the throat. Before departing in the spring, the birds grow in their breeding plumage, in which the males are strikingly patterned in black, gray, white, and yellow. They forage in trees, shrubs, and on the ground, looking for insects and berries, or flit out from the foliage to chase an insect.


From I-15 go east on Rancho Bernardo Road for 1.5 miles. Continue onto Espola Road. Go 1.6 miles. Turn left into the Blue Sky parking lot and drive to the end. Trailhead GPS: N33.01602, W117.02366

Explore more

Looking for more great hikes? Check out our Canyoneers page or purchase the book,
Coast to Cactus: The Canyoneer Trail Guide to San Diego Outdoors.

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