Atriplex parishii var. subtilis

(Stutz & G. L. Chu) S. L. Welsh
Rhodora 102: 423. 2001.
Common names: Subtle orach
EndemicConservation concern
Basionym: Atriplex subtilis Stutz & G. L. Chu Madroño 44: 184, figs. 1, 2a. 1997
Treatment appears in FNA Volume 4. Treatment on page 357. Mentioned on page 356, 358.

Stems erect, much branched, 1–3 dm, densely scurfy; branches opposite, often purple-reddish, neither ribbed nor striate; internodes 5–15 mm. Leaves mostly opposite, sessile; blade ovate-triangular to broadly ovate, 2–4 × 1–3 mm, mostly cordate-clasping, densely scurfy on both sides. Flowers of both sexes intermixed in axillary glomerules, but sometimes staminate clustered toward apex. Fruiting bracteoles persistent, deltoid, 2.4–2.8 mm and wide, margin with 1–3 pairs of irregular teeth, proximalmost usually larger and retrorse, apex shortly acuminate, with 2 longitudinal rows of tubercles on 1 or both surfaces. Seeds dark brown.


Phenology: Flowering late spring–fall.
Habitat: Saline depressions, often within or later growing in depressions of vernal pools
Elevation: 40-100 m

Discussion

Of conservation concern.

Atriplex depressa var. subtilis occurs with Allenrolfea occidentalis, Distichlis spicata, Centromadia pungens, Suaeda Moquin-Tandonii, Spergularia macrotheca, Frankenia salina, and Sporobolus airoides and other Atriplex spp. Stutz and Chu compared this variety with Atriplex depressa, with whose more northern range in the Central Valley it is contiguous. The leaves are relatively small and the stems are thin. Plants of var. subtilis appear very much like an elongated, gracile form of var. parishii.

Selected References

None.

Lower Taxa

None.

Stanley L. Welsh +
(Stutz & G. L. Chu) S. L. Welsh +
Atriplex subtilis +
Subtle orach +
40-100 m +
Saline depressions, often within or later growing in depressions of vernal pools +
Flowering late spring–fall. +
Endemic +  and Conservation concern +
Obione parishii +
Atriplex parishii var. subtilis +
Atriplex parishii +
variety +