Ambrosia tomentosa

Nuttall

Gen. N. Amer. Pl. 2: 186. 1818.

Endemic
Synonyms: Franseria discolor Nuttall Franseria tomentosa (Nuttall) A. Nelson
Treatment appears in FNA Volume 21. Treatment on page 17. Mentioned on page 11.

Perennials, 10–30+ cm. Stems erect. Leaves mostly alternate; petioles 8–25 (–35+) mm; blades elliptic to lance-elliptic, 50–80 (–180+) × 12–20 (–50+) mm overall, (1–) 2 (–3) -pinnately lobed (lobes ± deltate), bases cuneate, ultimate margins with ± deltate teeth, abaxial faces densely finely scabrellous (silvery gray), adaxial faces strigillose. Pistillate heads clustered, proximal to staminates; florets (1–) 2. Staminate heads: peduncles 2–9 mm; involucres saucer-shaped (with black nerves), 3–6+ mm diam., strigillose; florets 25–40+. Burs: bodies ± pyriform, somewhat flattened, 1.5–2.5 (–4) mm, finely scabrellous, spines (1–) 8–12+, scattered, stoutly conic, 0.5–1+ mm, tips straight.


Phenology: Flowering Jun–Sep.
Habitat: Seasonally wet clays or sands, disturbed sites
Elevation: (200–)1200–2100 m

Distribution

V21-19-distribution-map.gif

Ariz., Colo., Idaho, Ill., Iowa, Kans., Mo., Mont., Nebr., N.Mex., N.Dak., S.Dak., Tex., Utah, Wis., Wyo.

Discussion

Selected References

None.

Lower Taxa

None.
... more about "Ambrosia tomentosa"
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 +
Nuttall +
cuneate +
compound +  and simple +
elliptic to lance-elliptic +
8 cm80 mm <br />0.08 m <br /> (18 cm180 mm <br />0.18 m <br />) +
2 cm20 mm <br />0.02 m <br /> (5 cm50 mm <br />0.05 m <br />) +
5 cm50 mm <br />0.05 m <br /> (8 cm80 mm <br />0.08 m <br />) +
12mm;20mm +
winged;ribbed;winged;ribbed +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
scabrellous +
flattened;pyriform +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
barbellulate +  and barbellate +
purplish +  and whitish +
villous +, strigillose +, hispidulous +, glabrous +  and warty +
tuberculate +
globose +  and obovoid pyramidal pyriform obconic or fusiform +
fertile +  and bisexual +
Ariz. +, Colo. +, Idaho +, Ill. +, Iowa +, Kans. +, Mo. +, Mont. +, Nebr. +, N.Mex. +, N.Dak. +, S.Dak. +, Tex. +, Utah +, Wis. +  and Wyo. +
(200–)1200–2100 m +
stipitate-glandular +, glabrate +  and hairy +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Seasonally wet clays or sands, 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 +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
saucer--shaped +
conspicuous +
petiolate +  and sessile +
incurved;erect +
deltate +
dentate to pinnatifid or palmatifid +  and entire +
connate +  and distinct +
2-carpellate +
stipitate-glandular +, hirtellous +  and villous +
spatulate;linear +
membranous +
persistent +
0.2 cm2 mm <br />0.002 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
2.5 cm25 mm <br />0.025 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
Flowering Jun–Sep. +
5 +  and 16 +
unequal +  and subequal +
Gen. N. Amer. Pl. +
bearing subulate enations +, hairy +  and bristly +
convex;flat +
exalbuminous +
8 (?) +  and 12 (?) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
prostrate +  and decumbent +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Franseria discolor +  and Franseria tomentosa +
Ambrosia tomentosa +
Ambrosia +
species +
campanulate +  and cylindric +
straight +
deltate +
toothed +  and entire +
10 cm100 mm <br />0.1 m <br /> (30 cm300 mm <br />0.3 m <br />) +