Packera cynthioides (Greene) W.A. Weber & A. Löve
Family: Asteraceae
White Mountain Groundsel,  more...
[Senecio cynthiodes Greene,  more...]
Packera cynthioides image

Perennials, 20-40+ cm; rhizomatous (rhizomes horizontal to erect). Stems 1 or 2-3, clustered, densely lanate-tomentose or canescent, tufts of arachnoid tomentum in leaf axils, or glabrescent. Basal leaves (thick, leathery) petiolate; blades narrowly lanceolate or oblanceolate, 25-100+ × 5-20 mm, bases tapering, margins entire, subentire, dentate, or wavy (adaxial faces early glabrescent). Cauline leaves gradually reduced (sessile; lanceolate to oblanceolate, entire or wavy). Heads 10-30+ in open or congested, cymiform arrays. Peduncles 0 (or relatively reduced, then densely tomentose). Calyculi inconspicuous (bractlets red-tipped). Phyllaries (8-)13, green (tips red), 3-6 mm, densely tomentose proximally, glabrate distally. Ray florets (5-)8; corolla laminae 8-10+ mm. Disc florets 35-45+; corolla tubes 2.5-3.5 mm, limbs 3.5-4.5 mm. Cypselae 1-1.5 mm, glabrous; pappi 5-6 mm. 2n = 46.

Flowering late Jul-mid Sep. Loose rocky soils, steep slopes, subalpine and pine-juniper forests; 2200-2900 m; N.Mex.

Packera cynthioides blooms later than other Packera species at the same latitudes. It is noted by collectors as usually growing on north- or west-facing slopes in limestone-derived soils. Its cauline leaves are well developed and held at a shallow angle to the stem, giving the plant a more 'leafy' aspect than other members of the genus.