Ageratina rothrockii |
|
---|---|
Rothrock's snakeroot |
|
Habit | Perennials, (20–)40–70(–150) cm (slender, fibrous-rooted crowns, with slender rhizomes). |
Stems | ascending to erect, puberulent to glabrate. |
Leaves | opposite; petioles 2–20 mm; blades (3–5-nerved) lanceolate to lanceolate-ovate, mostly 3–6 × (1.5–)2–3 cm, bases obtuse to truncate, margins serrate to crenate, apices acute to acuminate, sparsely puberulent abaxially, mostly along nerves. |
Peduncles | 5–12(–20) mm, puberulent. |
Involucres | 5–7 mm. |
Corollas | white, lobes short-villous. |
Phyllaries | apices acute, abaxial faces glabrous or glabrescent, eglandular. |
Heads | clustered. |
Cypselae | sparsely and finely strigose-hirsute. |
Powell | on label]. |
2n | = 85 [ca. 100, fide A. M. |
Ageratina rothrockii |
|
Phenology | Flowering (Jul–)Aug–Oct. |
Habitat | Rocky slopes and ledges, in oak-juniper, pine-oak, pine, aspen, and spruce-fir woodland |
Elevation | 1700–2400 m (5600–7900 ft) |
Distribution |
AZ; NM; TX; Mexico (Chihuahua, Coahuila, Durango, Sonora)
|
Discussion | Ageratina rothrockii is similar to A. altissima, probably its western vicariant, and the two perhaps would be justifiably treated as conspecific. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 21, p. 550. |
Parent taxa | |
Sibling taxa | |
Synonyms | Eupatorium rothrockii |
Name authority | (A. Gray) R. M. King & H. Robinson: Phytologia 19: 216. (1970) |
Web links |