|
MANZANITA
Arctostaphylos spp.
big berry
manzanita photo © Lynn Watson
The Los Padres
National Forest is in one of the most botanically rich areas in
the country. Found within the California Floristic Province, an
area declared a global hotspot for biodiversity (particularly
plant diversity), the Los Padres is home to over 1,200 species
of plants, including a number of rare and sensitive plants found
nowhere else. Within the Los Padres, chaparral communities
harbor the greatest number of rare plants, five of which are
manzanita species, found only in specific areas of the forest.
There are over 60 species of manzanita in California, 11 of
which are found in the Los Padres. They range from shrubs only a
few feet tall to some as tall as 20 feet, and are all
characterized by reddish or orangish bark, gnarled trunks, and
waxy leaves. The plants produce bell-like white-to-pink flowers
in the winter and spring, and then produce apple-like fruits,
giving them their name “manzanita,” which means “little apple”
in Spanish. Native Americans would often use these fruits to
make meal and cider, and much of the wildlife of the chaparral,
including bears, deer, and squirrels, depend on these fruits for
food throughout the summer.
 Manzanitas
are adapted to particular fire patterns. While a few can
resprout from burls at the base of the shrubs, all have seeds
that are stimulated to germinate by chemicals in smoke or
charred wood. This does not mean, however, that manzanitas
“need” fire. It is a common misconception that chaparral plants
such as manzanitas need fire or are “fire dependent.” Manzanitas
can live for a very long time—hundreds of years by some
accounts—and their seeds can survive in the “seedbank” for
decades. This means that the plants never really need fire, but
they are prepared for it when it does occur, so long as it
doesn’t occur too frequently.
Today, chaparral is facing a different environment than it did
before Europeans arrived in California. Whereas lightning used
to only start fires once every few decades to centuries along
the Central Coast, now human-caused fires are occurring more
frequently, and this is having a negative effect on manzanitas
and chaparral in general. When manzanitas have time to build up
an adequate seedbank over many decades, there are sufficient
numbers of post-fire seedlings to restore the population.
Increased fire frequencies prevent this from occurring. In
addition, with those few manzanitas that sprout from burls
following a fire, a second fire soon after the first can kill
the new sprouts and permanently kill the burl.
This increased frequency of fire is especially harmful to our
rare and endemic manzanitas here in the Los Padres, including
Little Sur manzanita, Santa Margarita manzanita, Santa Lucia
manzanita, Arroyo de la Cruz manzanita, and Refugio manzanita,
which each have only a few populations occurring in the Los
Padres and lack the ability to resprout following fire. The U.S.
Forest Service has classified each of these five rare manzanita
species as “sensitive,” granting them special protections.
Arroyo de la Cruz Manzanita Arctostaphylos cruzensis
photo ©
Dieter Wilken
 Arroyo
de la Cruz manzanita is endemic (found nowhere else) to coastal
areas from northwest San Luis Obispo County to Southern Monterey
County and found in only two areas on the Los Padres National
Forest. This manzanita is small compared to more common
manzanita species, reaching less than a few feet in height, and
is described as a “spreading” evergreen shrub with reddish,
peeling bark and overlapping leaves. It does not have a basal
burl, however, and thus does not resprout after fire, making it
more sensitive to fire than some other manzanitas. Arroyo de la
Cruz manzanita occurs in a variety of habitats, including
chaparral, coastal scrub, conifer forest, and valley-foothill
grassland.
Little Sur Manzanita Arctostaphylos edmundsii
photo ©
Steve Matson
 Little
Sur manzanita is found in only a few places in the Los Padres.
It is endemic to Monterey County, only from Garrapata Creek to
Pfeiffer Point along the Big Sur coast. Little Sur manzanita is
described as a “low-mounded, small-leaved” manzanita. As with
Arroyo de la Cruz, Little Sur manzanita grows less than a few
feet tall and can grow wide, up to 11 feet across. This species
is characterized by shiny leaves with a yellow hue and compact
clusters of flowers. Little Sur manzanita occurs in coastal
bluff scrub and maritime chaparral on sandy terraces where it is
exposed to high winds, sea spray, and fog.
Santa Lucia Manzanita Arctostaphylos luciana
Santa Lucia Manzanita is
endemic to San Luis Obispo County. It is only found in the
southern portion of the Santa Lucia mountain range, and occurs
in five areas of the Los Padres. While overall the species is
rare on the forest, where it does occur it can be quite
abundant, forming large stands of purely Santa Lucia manzanita.
This manzanita is distinguished by overlapping, whitish leaves,
smooth bark, and soft, short hairs on young branches. It grows
larger than Little Sur or Arroyo de la Cruz manzanita, reaching
a height of over 16 feet, but as with these other species, lacks
a basal burl and regenerates only by seeding. Santa Lucia
manzanita is found in chaparral and woodland areas, on shale
substrates and outcrops on hill slopes.
Santa Margarita Manzanita Arctostaphylos pilosula
photo ©
California Native Plant Society
 Similar
to Santa Lucia manzanita, Santa Margarita manzanita is endemic
to San Luis Obispo County. It ranges from the southern Santa
Lucia Mountains to the hills between San Luis Obispo and Arroyo
Grande, and is found in two locations on the Los Padres National
Forest. Santa Margarita manzanita is characterized by dark,
smooth, red-brown bark, twigs with long or short bristly hairs,
and gray- to yellow-green leaves. It is found with chamise and
manzanita chaparral, as well as occasionally with conifers.
Refugio Manzanita Arctostaphylos refugioensis
photo ©
Lynn Watson
 Refugio
manzanita is endemic to the Santa Ynez Mountains of Santa
Barbara County. It ranges from near Lompoc to San Pedro Canyon,
and occurs in twelve known locations on the Forest. Refugio
manzanita can grow to about 16 feet tall and 11 feet wide, and
is characterized by 1.2-1.8 inch-long, heart-shaped, overlapping
leaves. As with the other rare manzanitas on the forest, refugio
manzanita does not have a basal burl. The species is found in
chapparal, sometimes mixed with woodland, in sandstone areas on
south-facing slopes and rideglines. Nearly all the refugio
manzanita on the forest was affected heavily by the 1955 Refugio
Fire, but the populations appear to have recovered well.
Protecting Rare Manzanitas and Chaparral in the Los Padres
ForestWatch is currently
working to protect manzanita on the Los Padres, as well as
chaparral in general, from overly-frequent burning and fuel
treatments like masticators that could destroy this important
ecosystem in the long-term. We are also working to improve fire
management on the Los Padres National Forest to better protect
rare species, sensitive chaparral communities, and wildlife.
Lastly, we are working to educate the community about fire in
the Los Padres through our series on “Fire Ecology in the Los
Padres National Forest.”
|
