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threetooth ragwort

flame ragwort

Habit Perennials, 10–30+ cm; taprooted (caudices ascending to erect). Perennials, 20–30+ cm; rhizomatous (rhizomes horizontal to erect, not branched), sometimes stoloniferous.
Stems

1 or multiple, clustered, usually glabrous, rarely sparsely floccose-tomentose, leaf axils sometimes tomentose.

1, irregularly lanate or tomentose.

Basal leaves

(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 orbiculate, ovate, oblanceolate, or rhombic, 20–50+ × 20–40+ mm, bases tapering, sometimes obtuse, margins coarsely dentate to crenate-dentate.

Cauline leaves

gradually reduced (± petiolate or sessile).

gradually to abruptly reduced (petioles broad-winged, clasping, blades obovate, bases tapering, margins irregularly dentate; distal sessile, linear to lanceolate, entire).

Peduncles

bracteate, glabrous or sparsely tomentose.

bracteate, lanate or tomentose distally.

Ray florets

8–10(–13);

corolla laminae 5–8+ mm.

8–10(–13);

corolla laminae (red-orange) 8–15+ mm.

Disc florets

45–60+;

corolla tubes 3–3.5 mm, limbs 4–5 mm.

35–65+;

corolla tubes 4–5 mm, limbs 5–6 mm.

Phyllaries

13 or 21, green, 6–10 mm, sparsely tomentose proximally, glabrous distally.

21, green (tips sometimes deep red), 8–10+ mm, densely tomentose proximally, sparsely tomentose distally.

Calyculi

inconspicuous.

conspicuous.

Heads

4–15+ in corymbiform arrays.

1–3+.

Cypselae

1.5–2.5 mm, glabrous or sparsely hirtellous on ribs;

pappi 5–6 mm.

1.5–2.5 mm, glabrous;

pappi 8–11 mm.

2n

= 46.

= 40, 46, 92.

Packera tridenticulata

Packera greenei

Phenology Flowering late May–early Jul. Flowering mid May–early Jul.
Habitat Open, dry areas, roadsides, gravelly or sandy slopes, short-grass prairies or sagebrush scrubs Dry, rocky, usually serpentine soils, open scrub-pine associations
Elevation 1000–2000 m (3300–6600 ft) 100–1600 m (300–5200 ft)
Distribution
from FNA
CO; KS; ND; NE; NM; OK; SD; TX; WY
[WildflowerSearch map]
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
Discussion

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.)

Of conservation concern.

Packera greenei is known from Coast Ranges of northern California. It has relatively large heads and bright orange-red ray corollas; its leaves are usually cyanic abaxially.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 20, p. 601. FNA vol. 20, p. 588.
Parent taxa Asteraceae > tribe Senecioneae > Packera Asteraceae > tribe Senecioneae > Packera
Sibling taxa
P. anonyma, P. antennariifolia, P. aurea, P. bernardina, P. bolanderi, P. breweri, P. cana, P. cardamine, P. castoreus, P. clevelandii, P. contermina, P. crocata, P. cymbalaria, P. cynthioides, P. debilis, P. dimorphophylla, P. eurycephala, P. fendleri, P. flettii, P. franciscana, P. ganderi, P. glabella, P. greenei, P. hartiana, P. hesperia, P. hyperborealis, P. indecora, P. ionophylla, P. layneae, P. macounii, P. malmstenii, P. millefolium, P. millelobata, P. multilobata, P. musiniensis, P. neomexicana, P. obovata, P. ogotorukensis, P. pauciflora, P. paupercula, P. plattensis, P. porteri, P. pseudaurea, P. quercetorum, P. sanguisorboides, P. schweinitziana, P. spellenbergii, P. streptanthifolia, P. subnuda, P. tampicana, P. texensis, P. tomentosa, P. werneriifolia
P. anonyma, P. antennariifolia, P. aurea, P. bernardina, P. bolanderi, P. breweri, P. cana, P. cardamine, P. castoreus, P. clevelandii, P. contermina, P. crocata, P. cymbalaria, P. cynthioides, P. debilis, P. dimorphophylla, P. eurycephala, P. fendleri, P. flettii, P. franciscana, P. ganderi, P. glabella, P. hartiana, P. hesperia, P. hyperborealis, P. indecora, P. ionophylla, P. layneae, P. macounii, P. malmstenii, P. millefolium, P. millelobata, P. multilobata, P. musiniensis, P. neomexicana, P. obovata, P. ogotorukensis, P. pauciflora, P. paupercula, P. plattensis, P. porteri, P. pseudaurea, P. quercetorum, P. sanguisorboides, P. schweinitziana, P. spellenbergii, P. streptanthifolia, P. subnuda, P. tampicana, P. texensis, P. tomentosa, P. tridenticulata, P. werneriifolia
Synonyms Senecio tridenticulatus, Senecio acutidens, Senecio compactus, Senecio densus, Senecio oblanceolatus Senecio greenei
Name authority (Rydberg) W. A. Weber & Á. Löve: Phytologia 49: 48. (1981) (A. Gray) W. A. Weber & Á. Löve: Phytologia 49: 47. (1981)
Web links