Packera tridenticulata
Packera cana
threetooth ragwort
woolly butterweed, woolly groundsel
1 or multiple, clustered, usually glabrous, rarely sparsely floccose-tomentose, leaf axils sometimes tomentose.
1 (per rosette, rosettes clustered), densely lanate or canescent.
(and proximal cauline, relatively thick and turgid) petiolate;
blades lanceolate or narrowly oblanceolate, 20–40+ × 5–15 mm, bases tapering, margins usually entire, sometimes sub-pinnatisect (apices subentire or dentate).
(and proximal cauline) petiolate;
blades ovate or elliptic to lanceolate, 25–50+ × 10–30 mm, bases tapering, margins entire or irregularly undulate to weakly dentate (abaxial faces persistently lanate, adaxial lanate to subglabrescent).
gradually reduced (± petiolate or sessile).
gradually reduced (petiolate or sessile, then weakly clasping; elliptic to lanceolate, entire or weakly dentate).
bracteate, glabrous or sparsely tomentose.
bracteate, usually densely lanate to floccose-tomentose (sometimes subglabrescent).
8–10(–13);
corolla laminae 5–8+ mm.
8–10 (or 13);
corolla laminae 8–10+ mm.
45–60+;
corolla tubes 3–3.5 mm, limbs 4–5 mm.
35–50+;
corolla tubes 2.5–3.5 mm, limbs 3.5–4.5 mm.
13 or 21, green, 6–10 mm, sparsely tomentose proximally, glabrous distally.
13 or 21, green, 5–8+ mm, densely tomentose.
inconspicuous.
inconspicuous (bractlets tomentose).
4–15+ in corymbiform arrays.
8–15+ in corymbiform arrays.
1.5–2.5 mm, glabrous or sparsely hirtellous on ribs;
pappi 5–6 mm.
2.5–3.5+ mm, glabrous;
pappi 4.5–7 mm.
= 46.
= 46, 92.
Packera tridenticulata
Packera cana
Packera tridenticulata is found throughout the central High Plains, in the foothills of the Rocky Mountains, and in high valleys to the west of the Rocky Mountain front. It tends to grow in clumps; the multiple stems arise from well-developed taproots. It apparently hybridizes with P. neomexicana var. mutabilis where their ranges overlap.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Packera cana is found in a wide variety of habitats and in a wide range of elevations throughout the western Cordillera and into the High Plains. Morphology is relatively uniform throughout its range except that alpine specimens are notably dwarfed and are often mistaken for P. werneriifolia, which differs by its consistently scapiform habit.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
KS Wildflowers, 
MN Wildflowers, 
PNW Herbaria, Turner Photog. 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
