Packera antennariifolia

(Britton) W. A. Weber & Á. Löve

Phytologia 49: 45. 1981.

Common names: Shalebarren ragwort
Endemic
Basionym: Senecio antennariifolius Britton in N. L. Britton and A. Brown, Ill. Fl. N. U.S. 3: 478,fig. 4040. 1898
Treatment appears in FNA Volume 20. Treatment on page 578. Mentioned on page 577.

Perennials, 20–40+ cm; rhizomatous (rhizomes branched, horizontal to suberect). Stems 1 (sometimes from rosettes, rosettes sometimes clustered), tomentose. Basal leaves petiolate; blades broadly lanceolate to elliptic or spatulate, 20–40+ × 10–20+ mm, bases tapering, margins entire or subentire to dentate distally (faces tomentose). Cauline leaves abruptly reduced (petiolate or sessile; narrowly lanceolate to sublyrate, sharply toothed to pinnatisect or entire). Heads 6–12+ in corymbiform arrays (lateral cymiform arrays sometimes originating in leaf-axils). Peduncles bracteate, densely lanate to sparsely tomentose. Calyculi inconspicuous. Phyllaries 13 or 21, green, 5–7 mm, densely tomentose (apices scarious). Ray-florets 8–10 (–13); corolla laminae 5–10 mm. Disc-florets 25–35+; corolla-tubes 3–4 mm, limbs 1.5–2 mm. Cypselae 1–1.5 mm, hirtellous on ribs; pappi 4–5 mm. 2n = 46.


Phenology: Flowering late Apr–late May.
Habitat: Slopes on shale barrens
Elevation: 300–800 m

Distribution

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Md., Pa., Va., W.Va.

Discussion

Packera antennariifolia is known only from shale barrens or shale-derived soils in central Appalachia. Plants growing on steep slopes have stouter, more horizontal caudices and more extensive fibrous roots than specimens from other locations. Specimens from shale-derived soils, not growing directly on shale barrens, have weakly lobulate leaves and noticeably less hairiness.

Selected References

None.

Lower Taxa

None.
... more about "Packera antennariifolia"
not tailed +, rounded +  and obtuse +
papillate +
truncate-penicillate +
scarious +
usually ovate +  and lance-linear +
indeterminate +  and determinate +
Debra K. Trock +
- Britton W. A. Weber & Á. Löve +
tapering +
Senecio antennariifolius +
2 cm20 mm <br />0.02 m <br /> - 4 cm40 mm <br />0.04 m <br /> +
broadly lanceolate;elliptic or spatulate +
1 cm10 mm <br />0.01 m <br /> - 2 cm20 mm <br />0.02 m <br /> +
winged;nerved;ribbed +
inconspicuous +
Shalebarren ragwort +
0.3 cm3 mm <br />0.003 m <br /> - 0.4 cm4 mm <br />0.004 m <br /> +
pale-yellow +  and deep orange-red +
0.5 cm5 mm <br />0.005 m <br /> - 1 cm10 mm <br />0.01 m <br /> +
cylindric +
fertile +  and bisexual +
fertile +  and bisexual +
Md. +, Pa. +, Va. +  and W.Va. +
300–800 m +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Slopes on shale barrens +
discoid +  and radiate +
in compact or congested to open corymbiform cymiform or subumbelliform , , , arrays +  and singly +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
0.5 cm5 mm <br />0.005 m <br /> - 1.2 cm12 mm <br />0.012 m <br /> +
campanulate;cylindric +
sessile +  and petiolate +
cauline +  and basal +
erect;recurved +
deltate +
dentate to pinnatifid +  and entire +
subentire +  and dentate +
2-carpellate +
0.4 cm4 mm <br />0.004 m <br /> - 0.5 cm5 mm <br />0.005 m <br /> +
densely lanate +  and sparsely tomentose +
Flowering late Apr–late May. +
linear +  and ensiform +
0.5 cm5 mm <br />0.005 m <br /> - 0.7 cm7 mm <br />0.007 m <br /> +
bearing subulate enations +, hairy +  and bristly +
conic;usually flat;convex +
exalbuminous +
prostrate +  and ascending +
appendaged +  and truncate +
papillate +
Compositae +
Packera antennariifolia +
species +
campanulate +
serrate +  and denticulate +
20 cm200 mm <br />0.2 m <br /> - 40 cm400 mm <br />0.4 m <br /> +
vine +, tree +, shrub +  and subshrub +
23 +, 22 +  and 20 +