Mentzelia packardiae
Mentzelia oreophila
Packard's blazingstar, Packard's mentzelia, Packard's stick-leaf
Argus blazingstar, mountain loving blazing star
multiple, erect, straight;
branches distal or along entire stem, distal longest or all ± equal, antrorse, upcurved; hairy.
blade 17–103 × 7.6–41.2 mm, widest intersinus distance 5.1–35.3 mm;
proximal oblanceolate to elliptic, margins serrate, teeth 6–22, slightly antrorse, 0.4–5.3 mm;
distal elliptic, lanceolate, or deltate, base clasping, margins serrate, teeth 6–16, slightly antrorse, 0.5–4.2 mm;
abaxial surface with complex grappling-hook trichomes, adaxial surface with complex grappling-hook and needlelike trichomes, both surfaces green, moderately hairy.
persisting or not.
petiole present or absent (proximal leaves), absent (distal leaves);
blade lanceolate to linear (proximal leaves), ovate to linear (distal leaves), to 10(–14) cm, margins dentate or entire (proximal leaves), entire (distal leaves).
green, ovate to elliptic, 4.3–8.3 × 1.9–3.2 mm, width 1/3–2/3 length, not concealing capsule, margins entire.
margins entire.
sepals 4–10 mm;
petals orange proximally, yellow distally, 10–20 mm, apex rounded to retuse;
stamens 20+, 4–13 mm, filaments monomorphic, filiform, unlobed;
styles 6–14 mm.
petals golden yellow, 7–14.5(–16.2) × 1.7–5.2 mm, apex rounded, glabrous abaxially;
stamens golden yellow, 5 outermost petaloid, filaments narrowly spatulate, slightly clawed, 5.3–11.1(–15.4) × 0.6–4.4 mm, with anthers, second whorl with anthers;
anthers twisted after dehiscence, epidermis smooth;
styles 3.8–8.1 mm.
narrow-cylindric, 8–35 × 2.5–4 mm, axillary curved to 45° at maturity, often prominently longitudinally ribbed.
cup-shaped, 5.8–9 × 5.2–8.8 mm, base rounded, not longitudinally ridged.
10–20, in 1 row distal to mid fruit, tan, dark-mottled or not, triangular prisms, surface ±smooth to minutely tessellate under 10x magnification; recurved flap over hilum absent;
seed coat cell outer periclinal wall flat to slightly convex.
coat anticlinal cell walls straight, papillae 6–17 per cell.
= 72.
= 22.
Mentzelia packardiae
Mentzelia oreophila
Mentzelia packardiae is the most narrowly distributed species in sect. Trachyphytum, known only from the Leslie Gulch area in eastern Malheur County. During most years, M. packardiae is predominantly limited to barren, ash-derived gravel slopes. A reported collection from Elko County, Nevada, is most likely from a large-flowered population of M. dispersa (N. H. Holmgren et al. 2005). Mentzelia packardiae can be distinguished from M. dispersa by its larger flowers with longer petals [10–20 mm versus 2–6(–8) mm] and styles [6–14 mm versus 2–3.5(–5) mm], and its wider capsules (2.5–4 mm versus 1–2.5 mm).
Mentzelia packardiae is listed as threatened by the Oregon Department of Agriculture and is in the Center for Plant Conservation’s National Collection of Endangered Plants.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Mentzelia oreophila is found in Inyo, Riverside, and San Bernardino counties, California, and Clark, Esmeralda, Lincoln, and Nye counties, Nevada. The California populations have a smaller stature than those in Nevada, and phylogenetic analysis indicated that the species is potentially polyphyletic.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
OR
Flora NW
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
CA
