Last Manzanita in San Francisco

Description and Ecology of Organism:

http://www.laspilitas.com/nature­-of­-california/
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franciscana-­franciscana­-manzanita

Arctostaphylos franciscana, commonly known as the Franciscan manzanita, is a low evergreen shrub in the heath family that grows to be
about 2 to 3 feet tall and contains very small brown fruit, about 0.24 to 0.32 in, and pink urn­shaped flowers that earned its name manzanita, or “little apple” (U.S. Fish & Wildlife Service). As chaparral plant species, a trigger for germination is fire. It is not known exactly what is needed for pollination or sustainable habitat since records were destroyed in 1940s, so these aspects can only be inferred. However, it is known the plant requires a pollinator like a bumblebee, a fruit dispersal community like rodents, and a soil mycorrhizal fungi community (U.S. Fish & Wildlife Service).

Geographic and Population Changes:

http://foundsf.org/index.php?title=Serpentine
_Grasslands_and_Maritime_Chaparral

Originally, these plants were found on the serpentine soils like Masonic and Laurel Hill Cemeteries and Mount Davidson. According to the USDA Forest Service, serpentine soils contains high levels of nickel and magnesium that is only able to support a few, unique species of plants tolerant to these conditions, like Arctostaphylos franciscana so there was low competition (USDA Forest Service).  However, these sites got destroyed for urban development in 1947 and the wild plant was not rediscovered until one was found on a construction site in 2009.

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The last wild plant was relocated and now currently resides in the San Francisco Presidio and is endemic to San Francisco.

Listing Date and Type: Arctostaphylos franciscana was listed as endangered under the ESA in February 2013.

Cause of listing and Main threats to its continued existence:
Arctostaphylos franciscana was thought to be extinct, so as soon as one wild plant was found it was quickly listed to protect it from actually becoming extinct. The main threat that nearly caused the plants extinction is habitat loss due to urbanization or purposeful habitat conversion from the plant’s native serpentine chaparral habitat to a habitat more suited for nonnative species.

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Also nitrogen from cars that run through the entirely of San Francisco with the exception of Presidio and Golden Gate Park have also been a detriment by increasing nonnative grass cover and further reducing the plant's native range. Arctostaphylos franciscana also faces disease and predation from potential threats like twig blight, P​hytophthora p​athogens, gnawing by voles, and larvae infestation from moths (U.S. Fish & Wildlife Service). Other threats include over trimming, altered fire regimes, loss of genetic diversity, loss of pollinators, climate change, hybridization, and a high probability of a negative stochastic event due to only having one wild plant remainding. (U.S. Fish & Wildlife Service)

Description of Recovery Plan:

https://sfforest.files.wordpress.com/2012/10/
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Since there is only one wild plant left, a lot of focus is going into protecting it from any disturbances that would threaten its survival as well as facilitating its growth in the botanical garden. The primary tacit for recovery will be to re establish populations of the species by taking cuttings from the wild plant and putting them into a habitat with appropriate soils, pollinators, seed dispersers, and soil mycorrhizal fungi (U.S. Fish & Wildlife Service). In order to achieve delisting, the plant must establish many self­sustaining populations in historical ranges or any other appropriate habitat in the San Francisco peninsula (U.S. Fish & Wildlife Service). The species has a high threat, but also high potential for recovery.

Works cited:

U. S. Fish & Wildlife Service.​ Recovery Outline for the Arctostaphylos franciscana (Franciscan manzanita). S​acramento. Retrieved 27 May 2015 from h​ttp://ecos.fws.gov/docs/ recovery_plan/Franciscan%20manzanita_Recovery%20Outline.​pdf

USDA Forest Service. “Serpentine Soils and Plant Adaptations”. United States Department of Agriculture. 2007. Web. Retrieved 1 June 2015 from h​ttp://www.fs.fed.us/wildflowers/ beauty/serpentines/adaptations.shtml