Chapter 12 Vegetation

California Kelp Forest.

Different than the vegetation in chapter 12 the native vegetation of Los Angeles is quite diverse since the county covers such a large area. From the beaches to the deserts the vegetation changes with the topography. Kelp thrives in regions of upwelling as well as regions with continuously cold, high-nutrient waters. Upwelling regions are regions where the ocean layers overturn, bringing cool, nutrient-rich bottom waters to the surface, especially rich in nitrogen and phosphorus. The California kelp forest flourishes because of the cool California current off the coast. Some species of kelp can grow as fast as half a meter a day, ultimately reaching 30 to 80 meters (100 to 260 feet).

Coastal Sage and Chaparral 

lemonade-berry

If one was to strip away the urban development within the basin the most common type of vegetation would be Coastal Sage and Chaparral. It grows in the canyons and Mountains of the Traverse Ranges and coastal sage scrub is a diverse and globally rare habitat type occurring on the terraces and foothills below 3, 000 feet.





This habitat type is characterized by low, a
romatic and drought-resistant  shrublands of black sage (Salvia mellifera), white sage (Salvia apiana), Munz’s sage (Salvia munzii), California sage (Artemisia californica), California buckwheat (Eriogonum fasciculatum), bush sunflower (Encelia californica), toyon (Heteromeles arbutifolia), lemonade-berry (Rhus integrifolia), and countless other shubs.

California buckwheat

All chaparral communities are adapted to fire. Some of the species crown spout, meaning they re-grow from root after fire. Others shed seeds which will only grow after fire. Fire plays an important role in most of the plant communities of Southern California, especially in those with high amounts sage and chaparral.

On average these areas burn every 15 to 20 years and these drought-resistant plants contain a huge amount of fuel, which lead to high heat fires that burst some of these plants into flames as the fire approaches. These wildfires usually happen after drought in late summer and early fall and they are pushed by the high pressure systems that park over the great basin, which pushes winds from the deserts down through the canyons warming them as they move out towards the Pacific. These winds are known as the Santa Ana's and they are the motor that pushes the famous fires that inundate the mountains and canyons, while the plant life is the fuel.

California Oak

The type of trees native to the Los Angeles region are California Oaks, Sycamores, and broadleaf conifers. They are interspersed in the interior valley's, canyon's, and throughout the Coast, Traverse, and Peninsular Ranges.

Sugar Pine

Moving into the higher elevation the native trees consist of eight different types pines. They include the Sugar, Jeffrey, Coulter, Ponderosa. Pinyon, Lodgepole, Gray, and Limber. They grow between 2,000 and 9,000 feet in elevation and are found in different areas of the San Gabriel and surrounding Mountain Ranges.

Joshua trees

Dropping out of the higher elevations into the Antelope Valley the vegetation changes once more and one would find Joshua trees, dry oak, California scrub, and in spring flowers such as the California poppy and silver lupine.

California Poppy

Sources:

http://digital-desert.com/antelope-valley/

San Gabriel Mountains, Plant Communities
http://tchester.org/sgm/plants/communities/index.html

http://www.fire.ca.gov/

http://www.eoearth.org/article/California_coastal_sage_and_chaparral