Chaparral

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Photo by Rick Halsey

The chaparral plant community normally inhabits the mesas and mountain slopes of the interior but also intermingles with the coastal sage scrub community along the coast, particularly on mesas and north-facing slopes where moisture is more plentiful. This community is composed of mainly sclerophyllous (meaning “hard-leaved” in Greek) shrubs with distinctive small, thick evergreen leaves which persist on the shrub for several years.

Chaparral sometimes forms an impenetrable thicket of vegetation with a large canopy five to fifteen feet high. This elfin forest lacks herbaceous understudy and is a haven for fauna and adventurous children who love to explore. Chaparral is California’s most extensive and characteristic plant community.

Chaparral is drought tolerant and has special adaptations to survive wildfires. Some shrubs, such as laurel sumac, live through the hot summer droughts by utilizing extensive root systems for gathering water deep underground. Others, such as California lilac, have shallow roots and smaller leaves with the ability to tolerate extreme water loss. Some chaparral species, like lemonade berry, have a waxy coating on their leaves which reduces water loss through evaporation. The chaparral community has been shaped by recurring wildfires, but is extremely sensitive to when and how frequently fires occur. Richard Halsey, a fire ecologist from the California Chaparral Field Institute (www.californiachaparral.com), says that, “Fire in the chaparral should be viewed as a disruptive force leading to the selection of fire survival strategies. For example, the seeds of many chaparral plant species require heat, smoke, or charred wood to stimulate germination. Does this mean the chaparral “needs” to burn? Not at all. Chaparral remains a vigorous plant community between fire events no matter its age.  Old-growth chaparral (75 years plus) continues to grow and support a dynamic population of animals. Chaparral plants have evolved fire-related adaptations in order to survive and carry on after a fire, not because they need to burn. If fires come too frequently, less than 20 years apart, the chaparral ecosystem can be converted to a weedy grassland dominated by invasive, non-native species.”

Torrey Pines State Natural Reserve has a very special and rare form of chaparral called maritime chaparral. It is has been shaped by ocean winds and the extra moisture it obtains from coastal fog. As you explore the Reserve, look for rounded hummocks of chamise overlooking the ocean and old, twisted California scrub oaks forming tunnels through which some trails meander.

The major shrubs of the chaparral are chamise (Adenostoma fasciculatum); manzanita (Arctostaphylos spp.); Nuttal’s scrub oak (Quercus dumosa); ceanothus (Ceanothus spp.); toyon (Heteromeles arbutifolia); and mountain mahogany (Cercocarpus minutifolus). The Nuttal’s scrub oak and warty-stemmed ceanothus (Ceanothus verrucosus) are characteristic of the Torrey Pines’ maritime chaparral plant community.

Next topic: Coastal sage scrub