(Jan 2022)  Page(s) 12.  Includes photo(s).
 
R. bridgesii, the currently accepted name for the Sierra ground rose, was discovered in 1857 by the English botanist Thomas L. Bridges. Its leaf surface is covered with a white tomentum but the hips are smooth.....R. calvaria ....Recognized as a synonym of R. bridgesii having the same botanical features....

(Jan 2022)  Page(s) 15.  Includes photo(s).
 
.....my nameless species erupting from rain-caked ashes last spring beneath a burned and sadly dead Pinus sabiana. Notice its leaves are glabrous green and elliptical in shape and about half the size of spithamea leaves. Also, its hips are in clusters and have a smooth surface without prickles. Its flower, with pinkish pistils, is similar to spithamea. ...I like to call it by the study name “Rosa pyrophilia” (fire-loving rose).

(Jan 2022)  Page(s) 10.  
 
....a rose growing at the Petrified Forest only two miles away as the crow flies, named Rosa sonomensis in 1891 by Edward L. Greene. (Today R. sonomensis is ranked as a synonym of R. spithamea.) On a survey of the Petrified Forest after the Tubbs Fire several years ago, I was walking its burned trails with owner Janet Angell when we came upon a large patch of R. sonomensis full of flowers. Janet was surprised to see them. She’d walked those trails many years and not seen rose flowers before. I explained that this rose is called a “firefollower.” With the overhead shading trees and shrubs reduced to ashes, the increase in potash and full sunlight initiates a flowering not seen under normally shady conditions. The low growing plants thrive, bloom and set lots of hips for years until overshadowed by surrounding shrub and tree growth. Gradually, they disappear beneath the soil, living as roots sending up only scattered sprouts with occasional flowers and rarely fruiting, patiently awaiting the next liberating fire.

(Jan 2022)  Page(s) 10-11, 14.  Includes photo(s).
 
p. 10: Away from streams, on dry hillsides among chaparral, and also in shady woods, is where California’s little Ground Rose, R. spithamea grows. Its dusty grey-purplish leaves are aptly described as “round, toothy leaflets like gear wheels.”... spithameas have bristles all over pedicel, hip and sepals...
There’s also a rare red-leaved form of R. spithamea we discovered in 1986 with the same whimsical “gear wheels” leaflets but solitary flowers and abundant reddish prickles. It was growing on the crest of the Mayacmas Mountains between the wine growing regions of Napa Valley and Sonoma County....

p. 14: .... R. granulata. (Today it’s considered a synonym of R. spithamea.)...This species has spiked glands (short sharp points) on the underside of its leaves (an obscure character) but the source of Greene’s “granulata” epithet. Botanists suspect R. granulata intergrades with R. californica. ....