Mentzelia packardiae
Mentzelia cronquistii
Packard's blazingstar, Packard's mentzelia, Packard's stick-leaf
Cronquist's blazingstar
solitary, erect, straight;
branches distal or along entire stem, proximal longer than distal, all usually extending to near the distal end of plant, antrorse, straight; hairy.
blade 21–101 × 4–10.7(–19.3) mm, widest intersinus distance 1.8–7.3(–12.6) mm;
proximal oblanceolate, lanceolate, or elliptic, margins dentate to pinnate, teeth or lobes 8–28, perpendicular to leaf axis, 1.2–6(–9) mm, always some more than 4 mm;
distal oblanceolate, elliptic, or lanceolate, base not clasping, margins dentate to pinnate, teeth or lobes 6–18, perpendicular to leaf axis, 1.1–5(–6.9) mm;
abaxial surface with simple grappling-hook, complex grappling-hook, and needlelike trichomes, adaxial surface with simple grappling-hook, needlelike, and occasionally complex grappling-hook trichomes.
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 or toothed to pinnate.
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, 9–16.6 × 2.5–5.1 mm, apex usually rounded, rarely acute, hairy abaxially;
stamens golden yellow, 5 outermost petaloid, filaments narrowly spatulate, slightly clawed, 7.3–13.2 × 1.8–4.3 mm, usually without, rarely with anthers, second whorl with anthers;
anthers straight after dehiscence, epidermis papillate or not;
styles 6.5–10 mm.
narrow-cylindric, 8–35 × 2.5–4 mm, axillary curved to 45° at maturity, often prominently longitudinally ribbed.
cup-shaped, 5.9–10.6(–11.4) × 5–7.6 mm, base tapering to 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 wavy, papillae 8–13 per cell.
= 72.
= 20.
Mentzelia packardiae
Mentzelia cronquistii
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.)
OR
Flora NW
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
