Packera tridenticulata
Packera contermina
threetooth ragwort
dwarf arctic butterweed, high alpine butterweed, northwestern groundsel
1 or multiple, clustered, usually glabrous, rarely sparsely floccose-tomentose, leaf axils sometimes tomentose.
1 or 2–3, clustered, bases floccose-tomentose, leaf axils tomentose, glabrous elsewhere.
(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).
(thick, fleshy) petiolate;
blades usually ovate, oblong, or spatulate, sometimes sublyrate, 20–50+ × 20–40+ mm, bases tapering (to winged petioles) or abruptly contracted to subcordate (petioles narrow), margins crenate, coarsely serrate, or subentire.
gradually reduced (± petiolate or sessile).
(often cyanic) gradually reduced (sessile, not clasping; lanceolate to linear, usually irregularly and shallowly lobed, rarely entire).
bracteate, glabrous or sparsely tomentose.
conspicuously bracteate, glabrous.
8–10(–13);
corolla laminae 5–8+ mm.
10–12;
corolla laminae 8–14+ mm.
45–60+;
corolla tubes 3–3.5 mm, limbs 4–5 mm.
55–75+;
corolla tubes 2.5–3.5 mm, limbs 3–4 mm.
13 or 21, green, 6–10 mm, sparsely tomentose proximally, glabrous distally.
21, deep red or green (tips reddish), 8–12+ mm, white-tomentose proximally.
inconspicuous.
conspicuous (tips of bractlets often purple).
4–15+ in corymbiform arrays.
1–2(–5+).
1.5–2.5 mm, glabrous or sparsely hirtellous on ribs;
pappi 5–6 mm.
1–1.25 mm, glabrous;
pappi 4–7 mm.
= 46.
= 160+.
Packera tridenticulata
Packera contermina
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 contermina grows in rocky areas and produces relatively short rhizomes and abundant thin fibrous roots. In mesic sites, the rhizomes are more robust and the fibrous roots are fewer. This taxon has been treated as part of P. cymbalaria or P. subnuda. Morphologic and cytologic data lend support to its recognition at species rank.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
KS Wildflowers
WildflowerSearch
iNaturalist
USDA Plants Database
BC
WA
Flora NW
PNW Herbaria
