Friday, September 28, 2012

Shrubs of Chino Hills State Park




As a native plant garden designer or home gardener, understanding how plants are naturally arranged in their environment is critical. Understanding what species occur together in their plant community takes this understanding a step further. Several plant communities exist within the boundaries of Chino Hills State Park in Orange County, California. The lower elevations in the western-most region of the park consist of primarily coastal sage scrub.

Coastal sage scrub exists primarily from San Diego to San Francisco. Several key plants occurring in this particular plant community are summer deciduous. These plants are valuable in the native plant garden and worth being included on your plant palette even though their summer dormancy presents challenges on an aesthetic level. There are many plants that make up the coastal sage scrub plant community, but none as predominately as Artemisia californica.

Artemisia californica (foreground above) also known by the common name California Sagebrush, is what is known as an indicator species. Basically this means it is the primary or dominant species in this particular plant community.

Artemisia californica thrives in full sun, preferring to grow on south, west-facing slopes. It requires little water and prefers no water in the summer months. A. californica relies on wildfire for seed germination, and is often claimed to be allelopathic. Plants that have this trait are known to secrete chemicals into the surrounding soil which inhibits other plants from growing in proximity.

This factor may account for its dominant status within the coastal sage scrub community. It is an important habitat plant for the endangered California Gnatcatcher which alone makes it a valuable plant for the native garden! It is also aromatic, filling the air space around it with an inviting aroma.

Along with California Sagebrush grows Encelia californica Coast Sunflower. From an aesthetic perspective this shrub is a perfect match with the aforementioned Artemisia californica. Its larger green leaves make for a nice contrast against the gray almost needle-like leaves of California Sagebrush.

This plant is a perennial typically growing to four feet in height and width and is a regular in coastal sage scrub. It exists in chaparral communities as well but to a lesser degree usually being replaced by its relative Encelia farinosa.

Encelia blooms and greens up quickly following the first rains of autumn and will continue to do so through early summer sporting large yellow daisy-like flowers. A favorite with local pollinators Coast Sunflower makes yet another wonderful edition to the native landscape, both aesthetically and functionally.

Salvia leucophylla Purple Sage is another regular in the park. Growing in abundance in North Orange County, this variety of salvia occurs from near sea level to 2,600 feet in elevation. Purple sage prefers full sun and grows to 5 feet in height and width.

Purple Sage is known for its abundant pale purple flowers and aromatic foliage and is a favorite with hummingbirds as well as pollinating insects who are drawn to the nectar it produces. Like Encelia, Salvia leucophylla makes an excellent addition to any sunny California garden with its pale gray leaves and lilac flowers.

Along with Salvia leucophylla, Salvia apiana White Sage is a regular too. As its epithet reflects, it is preferred by both native and European bees. This plant was–and still is–a favorite with local Native Americans who utilize the seed in a flower mix that has long been a food staple. In addition it has lesser known uses such as shampoo and tea! White sage is still used today as smudge by tribes in traditional ceremonies.

All the aforementioned shrubs are key components in a healthy coastal sage scrub garden. They address issues such as habitat restoration as well as desirable elements like aroma and aesthetic value. As a designer or home gardener it is challenging to utilize summer deciduous plants, but with a little forethought and proper placement they can contribute to a beautiful landscape that everyone can enjoy!