Pacific Chaparral - Code: Ne8A

Pacific Chaparral is the only truly Mediterranean habitat in the Nearctic. Chaparral experiences mild winters, when the temperature rarely drops below 32°F (0°C). The vast majority of annual precipitation falls during this period, accumulating an average of 10–17 in. (250–430mm). The summers are hot and dry, with little to no rainfall, and temperatures reaching upwards of 110°F (43°C). 
This habitat occurs mostly on steep slopes with well-drained, rocky soils, blanketing foothills and coastal bluffs in a nearly impenetrable thicket. The woody shrubs that dominate this habitat grow 5–15 ft. (1.5–4.5m) tall and are mostly evergreen and sclerophyllous.
Pacific Chaparral is an incredibly botanically diverse habitat, containing well over 1,400 documented plant species. With such high diversity, chaparral communities display a huge variation in species composition. Chamise (Adenostoma fasciculatum) is the most widespread and common shrub, and the closest to being a defining botanical feature. Other shrubs usually present in Pacific Chaparral include manzanitas (Arctostaphylos spp.), ceanothuses (Ceanothus spp.), oaks (especially Scrub Oak (Quercus berberidifolia)), Western Poison Oak (Toxicodendron diversilobum), mountain mahoganies (Cercocarpus spp.), and Toyon (Heteromeles arbutifolia). The diversity of herbaceous plants here is staggering and post-fire annuals account for nearly 20% of species in California’s flora. 
Pacific chaparral is famously fire-dependent. Under optimal conditions, this habitat experiences low-intensity ground fires every 5–20 years and high-intensity stand-replacing fires every 30–100 years. The characteristic flora is well adapted to these periodic burns and responds to fire in one of two ways. Re-sprouters have large subsoil burls, and the entire shrub regrows from this established root system after the destruction of aboveground vegetation. Obligate-seeders produce large quantities of seeds that remain dormant for long periods between fires. When exposed to fire and heat, these seeds germinate, replacing the parent plants consumed in the fire. A few species employ a mixture of these two strategies. Recovery is rapid and it only takes a few years for Pacific Chaparral to regrow a closed canopy.
One exception to this fire tolerance is the California Coastal Scrub subtype. California Coastal Scrub or “soft chaparral” is a short (2-6ft or .5-2m), dense shrub community found in the coastal lowlands. This habitat is comprised primarily of sages and buckwheats, especially California sagebrush (Artemisia californica), Black sage (Salvia mellifera), White sage (Salvia apiana), California buckwheat (Eriogonum fasciculatum), coyote brush (Baccharis pilularis), Coast brittle-bush (Encelia californica), and Golden yarrow (Eriophyllum confertifolium). These species are adapted for low frequency and low intensity fires. As fire frequency and intensity increases many of the characteristic species die out and are replaced by dense stands of Laurel sumac (Malosma laurina), prickly pear (Opuntia spp.) and lemonade berry (Rhus integrifolia).
While Pacific chaparral is well adapted to fire, the human cohabitants of the area are not. This habitat surrounds some of the most densely populated areas in the Nearctic, with destructive and dangerous consequences. Fast-moving intense fires in summer and fall are often followed by heavy winter rains and rapid erosion of the now-unstable soil. This fire-flood-landslide cycle is all too familiar in s. California and n. Baja California and means that careful management of this habitat, including regular and well-timed prescribed burns, is crucial for the well-being of the human population.