Ambrosia artemisiifolia

Linnaeus

Sp. Pl. 2: 988. 1753.

Common names: Petite herbe à poux
IllustratedEndemic
Synonyms: Ambrosia artemisiifolia var. elatior (Linnaeus) Descourtilz Ambrosia artemisiifolia var. paniculata (Michaux) Blankinship Ambrosia elatior (Walter) Rydberg Ambrosia glandulosa Ambrosia monophylla
Treatment appears in FNA Volume 21. Treatment on page 15. Mentioned on page 11, 18.

Annuals, 10–60 (–150+) cm. Stems erect. Leaves opposite (proximal) and alternate; petioles 25–35 (–60+) mm; blades deltate to lanceolate or elliptic, 25–55 (–90+) × 20–30 (–50+) mm, 1–2-pinnately lobed, bases cuneate, ultimate margins entire or toothed, abaxial faces sparsely pilosulous to strigillose, adaxial faces strigillose, both glanddotted. Pistillate heads clustered, proximal to staminates; florets 1. Staminate heads: peduncles 0.5–1.5 mm; involucres shallowly cupshaped (usually without black nerves), 2–3+ mm diam., glabrous or hispid to pilosulous; florets 12–20+. Burs: bodies ± globose to pyriform, 2–3 mm, ± pilosulous, spines or tubercles 3–5+, near middles or distal, ± conic to acerose, 0.1–0.5+ mm, tips straight. 2n = 34, 36.


Phenology: Flowering Jul–Oct.
Habitat: Wet to dry soils, disturbed sites
Elevation: 0–1000+ m

Distribution

V21-16-distribution-map.gif

Alta., B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.W.T., N.S., Ont., P.E.I., Que., Sask., Ala., Alaska, Ariz., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo.

Discussion

Hybrids between Ambrosia artemisiifolia and A. psilostachya have been called A. ×intergradiens W. H. Wagner. The name Ambrosia ×helenae Rouleau applies to hybrids between A. artemisiifolia and A. trifida.

Selected References

None.

Lower Taxa

None.
... more about "Ambrosia artemisiifolia"
sparsely pilosulous +  and strigillose +
not tailed +, rounded +  and obtuse +
coherent +  and distinct +
connate +  and distinct +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
spiciform +, racemiform +, paniculiform +, glomerate +  and corymbiform +
indeterminate +  and determinate +
John L. Strother +
Linnaeus +
cuneate +
compound +  and simple +
5.5 cm55 mm <br />0.055 m <br /> (9 cm90 mm <br />0.09 m <br />) +
3 cm30 mm <br />0.03 m <br /> (5 cm50 mm <br />0.05 m <br />) +
2.5 cm25 mm <br />0.025 m <br /> (5.5 cm55 mm <br />0.055 m <br />) +
lobed;deltate;lanceolate or elliptic +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
less globose;pyriform +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
barbellulate +  and barbellate +
Petite herbe à poux +
purplish +  and whitish +
tubular +  and more or less filiform +
villous +, strigillose +, hispidulous +, glabrous +  and warty +
tuberculate +
globose +  and obovoid pyramidal pyriform obconic or fusiform +
fertile +  and bisexual +
Alta. +, B.C. +, Man. +, N.B. +, Nfld. and Labr. (Nfld.) +, N.W.T. +, N.S. +, Ont. +, P.E.I. +, Que. +, Sask. +, Ala. +, Alaska +, Ariz. +, Ark. +, Calif. +, Colo. +, Conn. +, Del. +, D.C. +, Fla. +, Ga. +, Idaho +, Ill. +, Ind. +, Iowa +, Kans. +, Ky. +, La. +, Maine +, Md. +, Mass. +, Mich. +, Minn. +, Miss. +, Mo. +, Mont. +, Nebr. +, Nev. +, N.H. +, N.J. +, N.Mex. +, N.Y. +, N.C. +, N.Dak. +, Ohio +, Okla. +, Oreg. +, Pa. +, R.I. +, S.C. +, S.Dak. +, Tenn. +, Tex. +, Utah +, Vt. +, Va. +, Wash. +, W.Va. +, Wis. +  and Wyo. +
0–1000+ m +
stipitate-glandular +, glabrate +  and hairy +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Wet to dry soils, disturbed sites +
staminate +  and pistillate +
in corymbiform , glomerate , paniculiform , racemiform or spiciform , arrays +  and singly +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
membranous +  and scarious +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
hispid +  and pilosulous +
cup-shaped +
conspicuous +
petiolate +  and sessile +
alternate +  and opposite +
incurved;erect +
deltate +
dentate to pinnatifid or palmatifid +  and entire +
connate +  and distinct +
2-carpellate +
stipitate-glandular +, hirtellous +  and villous +
spatulate;linear +
membranous +
persistent +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
3.5 cm35 mm <br />0.035 m <br /> (6 cm60 mm <br />0.06 m <br />) +
2.5 cm25 mm <br />0.025 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
Flowering Jul–Oct. +
5 +  and 16 +
unequal +  and subequal +
bearing subulate enations +, hairy +  and bristly +
convex;flat +
exalbuminous +
Illustrated +  and Endemic +
prostrate +  and decumbent +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Ambrosia artemisiifolia var. elatior +, Ambrosia artemisiifolia var. paniculata +, Ambrosia elatior +, Ambrosia glandulosa +  and Ambrosia monophylla +
Ambrosia artemisiifolia +
Ambrosia +
species +
campanulate +  and cylindric +
straight +
0.1mm;0.5mm +
distal +, less conic +  and acerose +
toothed +  and entire +
60 cm600 mm <br />0.6 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
10 cm100 mm <br />0.1 m <br /> (60 cm600 mm <br />0.6 m <br />) +
150 cm1,500 mm <br />1.5 m <br /> (400 cm4,000 mm <br />4 m <br />) +