Much of the park is very steep, running from 400 ft. along Alpine Creek to over 1300 ft. at the highest point on Towne Ridge. This wide range of elevation accounts for some rather interesting natural features. In the lower elevations along moist ravines, many fern varieties are to be found, including the graceful five finger fern, sword fern, lady fern, gold back fern, polypody and woodwardia ferns. Also to be found along the moister slopes in great abundance are trillium, redwood violet, red clintonia and wild strawberry. In the more shady areas, carpets of redwood sorrel cover the redwood floor, and during the spring rainy season beautiful mosses and curious mushroom shapes appear throughout the park in glorious array. Even the troublesome poison oak plant is prevalent in many areas of the park, providing food and protection to the wildlife.
Trees common to the redwood forest include the coastal redwood. Douglas-fir, various varieties of oak and California bay trees. Trees found on the edge of the redwood forest in drier areas include madrone, California buckeye, and big leaf maple. The drier open areas abound in the springtime with a colorful display of beautiful wildflowers. Some of the prevalent types include sticky monkey flower, wood rose, sun cup and of course California poppy.
Many animal types, although not often seen, make their home in the park. A few include deer, raccoon, fox, opossum, bob-cat, woodpecker, jay, quail, garter and gopher snakes, curious banana slug, and many more.
Heritage Grove is a magnificent old-growth Redwood forest on Alpine Creek. As one wanders the network of trails under the towering giants, a sense of awe and tranquility permeates this unique enclave of forest that escaped the timber harvesting of earlier years. It is considered to have the largest Redwoods in the Santa Cruz Mountains.
Many of the grove's huge redwoods were scheduled to be logged until a citizen's group banded together to raise funds to purchase the grove so that the magnificent trees could be preserved forever. The county matched these funds and made acquisition possible.
The 37-acre preserve adjoins Sam McDonald Park to the northeast.
Heritage Grove Trail is accessible from the Sam McDonald parking lot (map) or from a small trailhead parking lot off Alpine Road (map). Heritage Grove Trail is open to pedestrians only. No horses are allowed on this trail.
Prepare for a safe and enjoyable visit to Sam McDonald Park and other San Mateo County Parks by being aware of your natural environment.