The last of the Manzanitas...
By Francisco A Ramirez
Description.
Pallid Manzanita (Arctostaphylos Pallida) also known as
Oakland Hills Manzanita, and Alameda Manzanita (http://en.wikipedia.org/wiki/Arctostaphylos_pallida)
is a member of the Ericacea family and is taxonomically complex, including over
100 different kinds of evergreen shrubs and trees. Species diversity is highest
along the coast of California, from Mendocino County to San Luis Obispo County.
Pallid Manzanita is an upright, evergreen, seeding shrub. It grows up to 13
feet in height with rough, gray or reddish bark which is one the most prominent
characteristics of this particular shrub. It has pale green leaves that cover
the stems by overlapping, they have a heart like shape that is characteristic
of this species. The leaves are pale green in color, covered with a whitish wax
coat, usually dull and smooth to the touch. The flowers bloom in clusters of
3-5 per branch, they are urn-shaped and usually have shades of white, rose, or
rose-white. The fruit is small, round, sticky and berry shaped. This exquisite
shrubs required excellent drainage but they can tolerate poor soil (http://ecos.fws.gov/docs/recovery_plan/Draft%20Recovery%20Plan%20for%20A.pallida.pdf)
Pallid Manzanitas are shade-intolerant which means that they need lots of sun
and the only way to propagate is by seeding. Bees and insect seem to be one of
the major pollinators.
Geographic and population changes
Pallid Manzanita are found in the northwest side of the
Diablo Range, in an area known as Oakland/Berkeley Hills, there has also been
occurrences a few miles of the San Francisco Bay. This region is known to have
a cooler, moist and more stable climate (Mediterranean climate) than the
climate farther inland.
Listing Date
Arctostaphylos Pallida (Pallid Manzanita) was listed as
endangered by the State of California in November 1979 and as a threatened
throughout its entire range on April 22, 1998.
Causes of listing and main threats
The Pallid Manzanita was listed because they have been
affected by an unidentified fungal pathogen ( Botryosphaeria species) which
affected 50% of the population. Also a soil-borne pathogen (Phytophthora
cinnamomi) has long been known to threat commercial and ornamental plants. Human
transport of contaminated soils is the primary reason for introducing this
disease into new areas. Another reason of why the Pallid Manzanita is threatened
is because of fire suppression policies and inactive or ineffective fire management
plans. The lack of frequent small fires to stimulate regeneration and reduce
fuel loads represented one of the major threats to the species.
Recovery plan.
Essentially the big picture of ensuring the survival of the
Pallid Manzanita is to minimize the spread of the soil-borne pathogen ( Phytophthora
cinnamomi), manage native and non-native vegetation that could shade the Pallid
Manzanita from getting sunlight, expand existing stands as well establish new
stands and ensure the stands are protected from incompatible uses and wildfire reduction
activities.
Work cited.
Draft Recovery Plan for Arctostaphylos Pallida ( pallida
manzanita), U.S. Fish and Wildlife Service Endangered Species,http://www.fws.gov/sacramento/es_kids/Pallid-Manzanita/es_kids_pallid-manzanita.htm
Kid’s species information, Sacramento Fish and WildfireOffice,http://ecos.fws.gov/docs/recovery_plan/Draft%20Recovery%20Plan%20for%20A.pallida.pdf
Arctostaphylos,http://en.wikipedia.org/wiki/Arctostaphylos_pallida
Center of Biological Diversity, Saving the Pallid Manzanita,
http://www.biologicaldiversity.org/species/plants/pallid_manzanita/
Pictures:
Map: www.summitpost.org
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