The owner of El Molino Central, located at Central Avenue and Sonoma Highway, did a magnificent job designing and building her restaurant. Since it first opened, in 2010, she has continued to improve the site. This stone wall was a later addition.
In a similar way that wood fences, or even buildings, are often built around trees,
the masons who crafted this wall incorporated the small tree right into the work.
The plant is heteromeles arbutifolia, or Toyon: https://www.calflora.org/cgi-bin/species_query.cgi?where-calrecnum=4140 (please correct if wrong.) This is an interesting plant to have at a restaraunt, since its toxicity is listed as MAJOR.