Navarretia rosulata (Marin County navarretia),  CNPS List 1B.2

by Doreen Smith

May brings us flowers of members of the genus Navarretia, Polemoniaceae.  The rarest is  Marin County Navarretia, Navarretia rosulata, a tiny flower that grows on open serpentinite scree and even in graded fire roads . Often associated with Sargent Cypress, (Hesperocyparis sargentii), plants can be abundant in the Mount Tamalpais area and the associated high ridges as far North as French Ranch, San Geronimo. The southernmost population is on the Old Stage Road above Bootjack Camp.
Once this species was confused with Navarretia heterodoxa but though they are similar vegetatively, that species has bright blue flowers, while Navarretia rosulata has white to lilac flowers in a neat bouquet with surrounding bracts.
We once thought it was an only-in-Marin endemic but recently another population was found by Jake Rugyt in Napa County, west of Lake Berryessa, miles disjunct from ours.

Not all the Marin Flora 2007 listed species of Navarretia are confirmed present. Navarretia tagetina may be from a mis-identified specimen. Whichever reference you consult about plants there are always some errors, people are not perfect, only human.

Photos by Vernon Smith

Navarretia rosulata – (Marin County navarretia)

 

Navarretia rosulata Marin County navarretia