Eupatorium ×pinnatifidum

Elliott

Sketch Bot. S. Carolina 2: 295. 1823.

Synonyms: Eupatorium eugenei Small Eupatorium pectinatum Small
Treatment appears in FNA Volume 21. Treatment on page 472. Mentioned on page 463.

Perennials, 40–100+ cm. Stems (from short caudices) single, densely branched distally, puberulent throughout. Leaves opposite (proximal) or alternate (nodes often appearing leafy, lateral buds develop leaves without axis elongation); sessile; blades (usually 1–2-pinnately or ternately lobed) or lobes pinnately nerved or 1-nerved, linear, 20–100 × 0.5–1.5 mm, bases narrowly cuneate to attenuate, margins entire or serrate, apices acute, faces puberulent, glanddotted. Heads in subcorymbiform to subpaniculiform arrays. Phyllaries 10–12 in 2–3 series, elliptic to oblong, 1–3.5 × 0.5–1 mm, apices acute to acuminate, shortly mucronate, abaxial faces puberulent, glanddotted. Florets 7–9; corollas 2–2.5 mm. Cypselae 1–1.5 mm; pappi of 20–30 bristles 2.5–3 mm. 2n = 20.


Phenology: Flowering Aug–Oct.
Habitat: Dry to wet areas, roadsides, around ponds, open pine woods
Elevation: 20–100 m

Distribution

V21-1181-distribution-map.gif

Ala., Fla., La., Miss., S.C., Tex., Va.

Discussion

Eupatorium ×pinnatifidum has been suggested to represent a series of recurrent hybrids between E. capillifolium or E. compositifolium and E. perfoliatum; molecular data, in addition to confirming that this combination occurs, also show that E. serotinum rather than E. perfoliatum is the second parent in at least some plants included in E. ×pinnatifidum.

Selected References

None.

Lower Taxa

None.

"fine" is not a number.

... more about "Eupatorium ×pinnatifidum"
not tailed +, truncate +, rounded +  and obtuse +
scarious +
usually ovate +  and lanceolate +
usually terete +  and clavate +
paniculiform +  and corymbiform +
subcorymbiform +  and subpaniculiform +
diffuse +  and dense +
indeterminate +  and determinate +
Kunsiri Chaw Siripun +  and Edward E. Schilling +
Elliott +
puberulent +
narrowly cuneate +  and attenuate +
enlarged +
1-nerved +  and nerved +
2 cm20 mm <br />0.02 m <br /> (10 cm100 mm <br />0.1 m <br />) +
dissected +, lobed +, toothed +  and entire +
ovate;lanceolate or linear +
0.5mm;1.5mm +
papillate +  and rugose +
(4-)5-angled;10-ribbed +
filiform +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
pinkish +  and white +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
prismatic +
fertile +  and bisexual +
Ala. +, Fla. +, La. +, Miss. +, S.C. +, Tex. +  and Va. +
20–100 m +
puberulent +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Dry to wet areas, roadsides, around ponds, open pine 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 +
alternate +  and opposite +
1-nerved +  and nerved +
2 cm20 mm <br />0.02 m <br /> (10 cm100 mm <br />0.1 m <br />) +
triangular +
0.5mm +  and 1.5mm +
serrate +  and entire +
2-carpellate +
persistent +
Flowering Aug–Oct. +
nerved +  and 2-3-nerved +
0.1 cm1 mm <br />0.001 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
10 +  and 12 +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Sketch Bot. S. Carolina +
bearing subulate enations +, hairy +  and bristly +
convex;flat +
exalbuminous +
appendaged +  and truncate +
hirsutulous +
papillate +
Eupatorium eugenei +  and Eupatorium pectinatum +
Eupatorium ×pinnatifidum +
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 +