Baccharis salicifolia
Baccharis pteronioides
mule's fat, mule-fat, seepwillow, water wally
yerba de pasmo
spreading to ascending, green to tan, simple proximally, sparingly branched distally, striate-angled, glabrous or minutely hairy, resinous and ± resin-varnished.
erect, terete, brittle, slightly striate, scabrous, stipitate-glandular, papillose-roughened.
present at flowering (abundant, well developed);
sessile or petiolate;
blades lanceolate-elliptic, slightly falcate (willowlike), 30–150 × 3–20 mm, bases attenuate, margins usually finely serrate from bases to apices, sometimes entire, apices acute to acuminate, faces glabrous, gland-dotted, ± resinous.
cauline (proximal withering before flowering, distal crowded in gascicles);
sessile;
blades linear to lanceolate or spatulate, 5–25 × 1–6 mm (stiff, coriaceous to fleshy), bases attenuate, margins sharply serrate (teeth 1–5 pairs, distal leaves often entire), faces glabrous, gland-dotted, resinous.
hemispheric; staminate 3–6 mm, pistillate involucres 3–6 mm.
campanulate; staminate 4–5 mm, pistillate 5–6(–7) mm.
50–150;
corollas 2–3.5 mm.
15–20;
corollas 4–5 mm.
(10–)17–48;
corollas 4–6 mm.
15–20;
corollas 4–5 mm.
ovate to lanceolate, 2–4 mm, margins scarious, erose or irregularly dentate, midribs distinct, medians green or reddish, apices (greenish or brownish purple) obtuse to acuminate (pale and dry, glabrous).
ovate to lanceolate, 1–5 mm, margins scarious, medians green, apices acute to acuminate, glabrous.
in terminal, compound corymbiform arrays (often involving distal branches).
(10–20+ on densely leafy lateral branchlets) in spreading racemiform arrays.
0.8–1.5 mm, 5-nerved, glabrous;
pappi 3–6 mm.
1.8–3 mm, 8–10-nerved, minutely papillose-glandular;
pappi 8–10 mm (bristles rigid).
= 18, 36.
Baccharis salicifolia
Baccharis pteronioides
Baccharis salicifolia is part of a complex that extends through the southwestern United States, Mexico, Central America, and South America to Argentina and Chile (J. Cuatrecasas 1968). It is recognized by the narrowly lanceolate, willowlike, finely serrate leaves with acute or acuminate apices, smallish heads in dense clusters, reddish phyllaries, and 5-nerved cypselae. By tagging and measuring individual plants throughout the year, D. H. Wilken (1972) demonstrated that B. salicifolia has distinct seasonal forms. The North American plants were once known as B. glutinosa or B. viminea, which were differentiated from each other by differences in woodiness, leaf size and serration, and flowering time.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Baccharis pteronioides is characterized by its shrubby stiff habit, rough gray bark, branches that are evenly spaced and often at 45° angles, fascicles of narrow sessile leaves, and heads in racemiform arrays on short leafy branches. The Mexican common name yerba de pasmo refers to an infusion of the leaves used to treat chills (pasmo) and sores; the plants are also said to be poisonous to cattle and sheep.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
OR
CalFlora
Flora NW
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
