Note added 5/29/15: My initial impression was that the inflorescence here wasn't secund...and under that assumption this plant would key to Streptanthus glandulosus ssp. arkii in Mayer and Beseda (2010) due to: perianth dark maroon; fruit ascending to erect; mid-cauline leaves < 5 × as long as wide, and coarsely toothed; inflorescence ± straight; and the Napa County locale (i.e. the northeast clade in their analysis). But the Jepson eFlora currently subsumes both S. g. ssp. arkii (= Mayer & Beseda's ''northeast clade'') and S. g. ssp. raichei (= Mayer & Beseda's ''northwest clade'') under S. g. ssp. glandulosus (= Mayer & Beseda's ''southern clade'').

However, Dean W. Taylor pointed out to me that the inflorescence here is secund (''although one flower got its genetic signal crossed, and the uppermost few buds often go genetically unprogrammed and thus return to spiral orientation''). And indeed the flowers and fruit all appear to lie on one side of a(n imaginary) vertical plane through the two oppositely directed flowers...so I'd have to agree that the inflorescence is secund. Thus this keys in both the Jepson eFlora key and that of Mayer & Beseda (2010) to S. glandulosus ssp. pulchellus.

But that ID is problematic for the following reasons:

1) First off, the best choice at the succeeding couplet is ''sepals rose to lavender'' (TJM2) or ''sepals red to reddish purple'' (M&B) as in typical pulchellus. However, the color of the sepals in this plant appear much closer to the dark maroon color typical of arkii (M&B) and of S. g. ssp. glandulosus (à la TJM1, before the latter was enlarged by incorporating the more pink-flowered S. albidus peramoenus via synonymy in TJM2). Note, however, that the color of the S. g. pulchellus image here does approach the dark maroon of my post here.

2) The fruits in S. g. pulchellus are described in both TJM2 and M&B as ''curving upward'' and ''divaricate to ascending''), whereas in my images the maturing fruits appear more-or-less straight and ascending to erect...in accord with M&B's description for subspecies arkii. (The JM2 description for S. g. ssp. g. covers the gamut of fruits straight to recurved and reflexed to ascending! ).

3) The length-to-width ratio of the leaves (< 5:1) and their margination (large teeth) seem in accord with the description of arkii given by M&B.

4) Oat Hill Mine Rd is in the stated range of arkii and outside the stated Mt. Tamalpais range of pulchellus.

5) Dean Taylor mentioned the pedicels of the Oat Hill Mine Rd plant here seem long for pulchellus.

Per the tacit guidelines of CalPhotos, I figure I should try to fit this post into the current Jepson eFlora circumscription, with some wiggle-room allowance for 'variation' (the ever-present bane of taxonomists desirous of all things fitting in well-separated groupings!). In that context, it seems to me the best fit overall is with S. g. g. (per Jepson) or S. g. arkii (per M&B), rather than with S. g. pulchellus.

Dean Taylor suggested this might be an undescribed race...but I don't have enough experience or evidence to promote that alternative over the explanation of 'variation'. So it still seems to me that the best resolution among the somewhat conflicting alternatives here is S. glandulosus ssp. glandulosus (per JM2), or S. g. ssp. arkii (per Mayer & Beseda (2010) .

Speaking of variation:

i) Note the inflorescence in this S. g. pulchellus post is not secund.

ii) The inflorescence in fruit (or ''infructescence''...for those who enjoy botanical terminology :-) in this image is strongly secund and divaricate (= spreading perpendicular to the inflorescence axis)...but nearly all the fruits are straight rather than ''upwardly curved''. On the other hand, the fruits in this image are indeed curved upward and divaricate, but only very weakly secund (i.e. to one side of a vertical plane through the infl axis...but directed at many divergent angles).

iii) The post of S. glandulosus ssp. glandulosus here appears to have a secund inflorescence, although the image does not show the entire inflorescence.