Ageratina paupercula

(A. Gray) R. M. King & H. Robinson

Phytologia 19: 215. 1970.

Common names: Santa Rita snakeroot
Basionym: Eupatorium pauperculum A. Gray Proc. Amer. Acad. Arts 17: 205. 1882
Treatment appears in FNA Volume 21. Treatment on page 551. Mentioned on page 548, 552.

Perennials or subshrubs, to 100 cm. Stems erect, puberulent to glabrate. Leaves opposite; petioles 3–15 mm; blades narrowly to broadly lanceolate, (2–) 3–7 × 0.5–1.5 cm, margins coarsely and remotely serrate, apices long-acuminate, abaxial faces sparsely pubescent. Heads clustered. Peduncles 2–6 mm, puberulent. Involucres 2.5–3 mm. Phyllaries: apices acute, abaxial faces puberulent-hispidulous. Corollas white, lobes sparsely hispid-villous. Cypselae glabrous.


Phenology: Flowering Mar–May.
Habitat: Rocky slopes, crevices, gravelly, sandy streambeds, pine-oak woodlands
Elevation: 1000–1800 m

Discussion

Ageratina paupercula is recognized by its early spring flowering, relatively small and usually narrowly lanceolate and acuminate leaves, relatively small heads in clusters, and relatively small (1.2–1.4 mm versus mostly 2–3 mm in other species), glabrous cypselae.

Selected References

None.

Lower Taxa

None.

"fine" is not a number.

... more about "Ageratina paupercula"
puberulent-hispidulous +  and pubescent +
not tailed +, truncate +, rounded +  and obtuse +
acute;long-acuminate +
scarious +
usually ovate +  and lanceolate +
usually terete +  and clavate +
indeterminate +  and determinate +
Guy L. Nesom +
(A. Gray) R. M. King & H. Robinson +
decurrent +
enlarged +
Eupatorium pauperculum +
3(-5)-nerved +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
3 cm30 mm <br />0.03 m <br /> (7 cm70 mm <br />0.07 m <br />) +
dissected +, lobed +, toothed +  and entire +
lanceolate +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
papillate +  and rugose +
(4-)5-angled;10-ribbed +
Santa Rita snakeroot +
scabrellous +
fusiform +  and prismatic +
fertile +  and bisexual +
Ariz. +  and Mexico +
1000–1800 m +
puberulent +, pilose +, hispidulous +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Rocky slopes, crevices, gravelly, sandy streambeds, pine-oak woodlands +
indeterminate +
each +  and sessile +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
campanulate +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
hispid-villous +
lanceolate +  and lance-linear +
2-carpellate +
persistent +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Flowering Mar–May. +
2-nerved +  and 0-nerved +
8 +  and 30 +
subequal +  and unequal +
bearing subulate enations +, hairy +  and bristly +
exalbuminous +
puberulent +  and glabrate +
appendaged +  and truncate +
hirsutulous +
papillate +
Compositae +
Ageratina paupercula +
Ageratina +
species +
obconic +  and campanulate +
0 cm0 mm <br />0 m <br /> (100 cm1,000 mm <br />1 m <br />) +