Rainbow Manzanita (Arctostaphylos rainbowensis) | Botanical Pride

Greetings, guys, gals, and non-binary pals!  Welcome back to the blog, or welcome if you’re new here.  

As June is LGBTQ+ pride month, the next several posts will be relevant to that topic, whether regarding rainbows or historical/cultural associations.  I put out a call on Twitter for suggestions and this suggestion comes from Raphael Mazor (https://twitter.com/rmazor).

Today, we’re talking about the only plant to currently have “rainbow” in its scientific designation: The Arctostaphylos rainbowensis, or Rainbow Manzanita.  This dicot shrub is native and endemic to California (4,5), existing exclusively in the far southern portion of the state, specifically between northern San Diego to southern Riverside counties.  This shrub is particularly fond of the Peninsular Ranges (1,4), and is named after Rainbow, California, where it is most often found, situated in the chaparral forests of the Santa Ana Mountains (6).  Between living in a highly restricted ecosystem and having that limited ecological footprint threatened by development and natural occurrences alike, the A. rainbowensis has a G2 conservation status classification, indicating that it’s an imperiled species (7).  This means that while not in imminent danger of extinction, there are still many concerns surrounding the species' habitat and continued environmental protection.

Outside of its native ecosystem, this shrub is grown as an ornamental plant, though it is extremely rare for it to be successfully cultivated (2). 

The A. rainbowensis was only recognized as a separate, distinct species in 1994, though first noted and collected in 1973.  Previously, the A. rainbowensis was thought to be either from a "disjunct population of Arctostaphylos peninsularis, or alternately a hybrid between A. glauca and Arctostaphylos glandulosa" (3).  Depending on growing conditions (soil composition, terrain, and environmental factors), the shrub can grow from anywhere between one and four meters tall (2,3,4). 

Till next time,

Kate