Chaparral of California
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California cities that occur in Chaparral.
Chaparral is far from uniform so it is not possible to 'connect
the dots'. I've drawn out the areas that could be in the range of
the Chaparral plant community.
There's
been a push by fire departments and insurance companies to remove
Chaparral in urban interface areas. Here are some points to
ponder.
1. Firemen don't usually die in brush fires, they die in grass
fires. Weedy fields burn faster than you can drive, never mind
run. By the time you figure out a grassy area is burning, it is
over. It's like standing in the middle of a tunnel with a high
speed train coming. Remove the alien, annual grasses and weeds;
manage the native brush.
2.
To repeat (ad nauseum!), there is almost no erosion in clean
Chaparral; there are large mud slides in areas of Chaparral that
have been converted to grass. In the large lysimeter study that
was done at San Dimas, California, the conclusion was: removing
brush would lead to enormous erosion problems. But fire insurance
commonly doesn't cover mud slides....
3.
Fire departments can easily put out grass fires. Tankers knock
them down; tractors put them out. Brush fires are much bigger,
scarier and require days of work. They also are slower. In clean
Chaparral (without the presence of, you guessed it, alien annual
grasses) you usually have time to leave. Mix some grass and weeds
into Chaparral and you have something that will start burning more
easily, and burn fast and very hot.
4. A properly managed Chaparral slope is very hard to burn (try
back firing it!); erosion is very low and and the Chaparral can
survive in extreme drought. Leave no dead limbs or debris other
than very small twigs and leaves. Thin the solid, dense stands of
shrubs to about 50% to 30% of the original numbers, depending on
your site conditions. Leave all of the Toyon
(Heteromeles arbutifolia) and remove most (not all) of
the Chamise
(Adenostoma fasciculatum) or Red
Shanks (Adenostoma sparsifolium).
5. Most brush fires occur at the end of a drought when everyone
is on rationing and can't water their plants. The 'firesafe'
non-natives turn into dead twigs that burn very well, thank you.
A
chaparral hillside recovering after a fire..
WITH NO WEEDS PRESENT!
Serpentinite soils
This
picture of a serpentine grassland in the central coast ranges of
California, adjacent to Chaparral, demonstrates the effect of this
soil type on vegetation. In some areas there exists nearly
straight serpentinite soils. Where the conditions would normally
dictate Chaparral you end up with a serpentine grassland. We do
not separate this as a plant community because the serpentine
plant community is usually the plant community that is supposed to
be there, minus the plants that cannot tolerate serpentine. On
real 'raw' serpentine areas this will be nearly all low,
herbaceous seasonal forbs, grasses and bulbs that also occur in
the adjacent Chaparral plant community. The serpentine soil
supports an extreme form of the Chaparral plant community.
My
dream hammock.
What to do if you
are in a fire area.
A list
of California native plants that tolerant of deer and fire ...
Wildfire
and California Native Plants, design, native landscaping
Planting
seed or plants for erosion after a wildfire.
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This is a very diverse plant community that can survive almost
on winter blowing fog/clouds in Anza, California, or be adjacent
to our very wet Redwood
Forest.
Chaparral is also loosely called brushland, or brush.
The only consistent pattern is: Chaparral usually does not
occur on good soil. BUT, it is more than likely that the early
settlers removed all the chaparral as nasty brush from ALL the
flatter richer soils so the only places Chaparral is left is on
the slopes and poorer soils. So, for now, Chaparral exists on
rocky, shallow soils overlaying a subsoil that is clay or rock
that commonly holds moisture.
The variable being soil depth, these three close plant
communities transition: from Grassland (the shallowest soil), to
Chaparral (intermediate in soil depth) to Oak Woodland (the
deepest soil, deep enough to support trees, often over 4 feet in
depth).
Chaparral occurs in areas of occasionally freezing winters (to
-5F(-20C)), but usually mild, moist winters and dry, hot summers
(commonly above 100F (38C). During the weather patterns that
existed when the Spanish explorers came to California, the
Chaparral was REAL cold. The temperatures were probably -20F
(-29C) along much of the central coast ranges. In most of
California the climate is called Mediterranean, which corresponds
with the Chaparral plant community.
What
are characteristics of chaparral shrubs?
Sclerophyllous (hard-leaved) plants commonly form the
foundation of this plant community. They have small, hard leaves,
that roll up, under, or fall off during the normal summer drought.
Then there are the many evergreen bushes with extensive root
systems that hold on to their leaves for dear life. These are very
efficient plants that defy the PhD's with their sophisticated
machines. These plants consistently draw more moisture from the
ground than comes down in rain. There is no measurable runoff in a
chaparral plant community. Oh, you get creeks because of springs
and other slow releases, but not runoff directly from the hillside.(Patric, James. 1974)
What elevation is chaparral found in?
Chaparral usually isn't in the real lowlands. In places like
Malibu it starts out at about 500 ft. up slope, with Coastal Sage
Scrub only living in a narrow band right next to the water. On the
other hand, Coastal Sage Scrub runs up to about 4000 foot in
Julian, California, and some areas around Riverside and Highland.
In some areas like Julian, Chaparral exists in a narrow strip,
between Coastal Sage Scrub and Yellow Pine Forest. So elevation is
probably not a great predictor for Chaparral.
The
aspect of a hillside can make a great difference in the makeup of
the chaparral. North facing slopes are a lot moister and can
support Toyon
(Heterromoles arbutifolia), Manzanita
(Arctostaphylos spp.), Scrub
oak (Quercus spp.), Pitcher
sage (Lepechinia spp.), Climbing
Penstemon (Kekiella cordifolia, K.
antirrhinoides), and Poison oak (Toxicodendron
diversilobum). The dry arid south facing slope is dominated by
Chamise
(Adenostoma spp.),
Black sage (Salvia melifera), Yucca
(Yucca spp.), Woolly
blue curls (Trichostema lanatum) and Bush
poppy, (Dendromecon rigida).
Delineating characteristics of this plant
community
1. Fire is a major factor in the dynamics of this Chaparral
plant community, and plants are adapted to fire, ie.
crown-sprouting shrubs, and annual fire- followers.
WEEDS AND HUMAN CARELESSNESS HAVE CHANGED the FIRE FREQUENCY!!!
Normal fire frequency should be about 100-400 years, depending
on the Chaparral type and location. The presence of weeds, and
human carelessness has increased the fire frequency to as little
as six months. Many of the native plants that live in Chaparral
require years to develop the right conditions for their seeds to
germinate. Weed seeds can germinate and set seed in as little as a
few months. Once certain cascading events are set into motion,
namely frequent fires, in addition to the presence of weeds, in a
Chaparral plant community, you have a recipe for plant community
degradation and destruction. Suppress fire in the Chaparral plant
community for as long as you possibly can and remove the weeds,
and you might keep the Chaparral plant community intact.
2. This plant community is highly adapted to very long dry
spells, but unlike desert plant communities, areas of Chaparral
can have very wet winters, also. 30-40 inches of rainfall in two
months is common and no rain for 1-2 years has also been
documented.
California
Chaparral
This plant community exists in many areas of the coast ranges
and on the western slopes of the Sierra Nevada mountains. It is
also found on the western and eastern slopes of the southern
California mountains. It is 'hard' brush that doesn't rely as much
on summer fog drip that the 'soft' Coastal Sage Scrub does, and it
is adapted to heat and drought. If you know where the fog belt is
for an area, the rainfall, the soil type, and what the summer
temperatures are, it is pretty easy to guesstimate where Chaparral
should be. Precipitation of 30-90 cm, or less and you'll have
either Shadscale Scrub, Joshua Tree Woodland, (in hotter areas) or
Pinyon-Juniper Woodland (in colder areas). Higher amounts of
rainfall make for Mixed Evergreen Forest or Yellow Pine Forest,
and coastal fog and cooler summer days means Coastal Sage Scrub
(soft brush). If Chaparral isn't where it should be, it was
probably cleared. The more accessible areas have been cleared by
the mile. Fortunately, Chaparral still occurs in large areas that
were hard to reach by tractor.
The Chaparral (brushland) is usually a successional plant
community that gradually moves to oak and pine forest, if the soil
depth supports it, even if the amount of rain falling from the sky
does not change. Pretty cool, huh? Over time, just the presence of
the Chaparral can change the pH one unit, can effectively double
the precipitation, and can produce a litter layer (mulch layer of
leaves) in which the pines and oaks can germinate. That is, if it
doesn't burn for decades or, maybe centuries, no one really knows
the time line.
One of the many points the “tecchies” out there miss, that
has been pointed out repeatedly by the old naturalists, is that
the Chaparral plant community 'creates' moisture. There is almost
no runoff from chaparral sites, and the soil only becomes dry on
'real' drought years. Most of the time soil moisture ranges from
moist (not wet) to slightly dry. This is a great growing bed for
the oaks, pines and trees of higher rainfall areas. The higher the
brush gets, the more blowing fog or clouds are caught, and the
more fog is created from this catch.
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