Eupatorium lancifolium

(Torrey & A. Gray) Small

Fl. S.E. U.S., 1167. 1903.

Common names: Lanceleaf thoroughwort
Endemic
Basionym: Eupatorium parviflorum var. lancifolium Torrey & A. Gray Fl. N. Amer. 2: 85. 1841
Synonyms: Eupatorium semiserratum var. lancifolium (Torrey & A. Gray) A. Gray
Treatment appears in FNA Volume 21. Treatment on page 468. Mentioned on page 464, 469, 473.

Perennials, 40–100+ cm. Stems (from short rhizomes) single, branched distally, usually glabrous or glabrate, sometimes pilose. Leaves usually opposite (distal sometimes alternate); sessile or subsessile (petioles to 5 mm); blades 3-nerved from bases, lanceolate to lance-linear, 30–50 × 5–13 mm, bases narrowly cuneate, margins serrate, apices acute, faces glabrous adaxially, sparsely pilose abaxially, densely glanddotted. Heads in corymbiform arrays. Phyllaries 7–10 in 2–3 series, elliptic, 1–4.5 × 0.2–0.8 mm, apices rounded, abaxial faces pilose, glanddotted. Florets 5; corollas 2.5–3 mm. Cypselae 2.5–2.8 mm; pappi of 30–40 bristles 3.5–4 mm. 2n = 20.


Phenology: Flowering Aug–Sep.
Habitat: Dry, rolling terrain, clay soils, shade to sun, shortleaf pine and oak woods
Elevation: 50–200+ m

Discussion

Eupatorium lancifolium has been combined with E. semiserratum or listed within it as a subspecies; it differs in its habitat as well as in having leaves that are somewhat smaller, typically a dull blue-green (in contrast to yellow-green in E. semiserratum), and 3-nerved from bases of blades.

Selected References

None.

Lower Taxa

None.

"fine" is not a number.

... more about "Eupatorium lancifolium"
not tailed +, truncate +, rounded +  and obtuse +
rounded;acute +
scarious +
usually ovate +  and lanceolate +
usually terete +  and clavate +
diffuse +  and dense +
indeterminate +  and determinate +
Kunsiri Chaw Siripun +  and Edward E. Schilling +
(Torrey & A. Gray) Small +
puberulent +
cuneate +
enlarged +
Eupatorium parviflorum var. lancifolium +
3 cm30 mm <br />0.03 m <br /> (5 cm50 mm <br />0.05 m <br />) +
dissected +, lobed +, toothed +  and entire +
lanceolate;lance-linear +
0.5 cm5 mm <br />0.005 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
papillate +  and rugose +
(4-)5-angled;10-ribbed +
filiform +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Lanceleaf thoroughwort +
pinkish +  and white +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
prismatic +
fertile +  and bisexual +
Ala. +, Ark. +, La. +  and Tex. +
50–200+ m +
pilose +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Dry, rolling terrain, clay soils, shade to sun, shortleaf pine and oak woods +
in usually determinate , rarely indeterminate , arrays +  and singly +
indeterminate +
each +  and sessile +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
obconic;ellipsoid +
subsessile +  and sessile +
triangular +
2-carpellate +
persistent +
Flowering Aug–Sep. +
nerved +  and 2-3-nerved +
0.1 cm1 mm <br />0.001 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
7 +  and 10 +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
Fl. S.E. U.S., +
bearing subulate enations +, hairy +  and bristly +
convex;flat +
exalbuminous +
pilose +, glabrate +  and glabrous +
appendaged +  and truncate +
hirsutulous +
papillate +
Eupatorium semiserratum var. lancifolium +
Eupatorium lancifolium +
Eupatorium +
species +
campanulate +
toothed +  and entire +
40 cm400 mm <br />0.4 m <br /> (100 cm1,000 mm <br />1 m <br />) +
vine +, shrub +  and subshrub +