Avena fatua

L.
Common names: Wild oats Folle avoine
Synonyms: Avena fatua var. glahrescens Avena fatua var. glabrata
Treatment appears in FNA Volume 24. Treatment on page 735.
Please click on the illustration for a higher resolution version.
Illustrator: Cindy Roché

Copyright: Utah State University

Plants annual. Culms 8-160 cm, prostrate to erect when young, becoming erect at maturity. Sheaths of the basal leaves with scattered hairs, upper sheaths glabrous; ligules 4-6 mm, acute; blades 10-45 cm long, 3-15 mm wide, scabridulous. Panicles 7-40 cm long, 5-20 cm wide, nodding. Spikelets 18-32 mm, with 2 (3) florets; disarticulation beneath each floret; disarticulation scars of all florets round to ovate or triangular. Glumes subequal, 18-32 mm, 9-11-veined; calluses bearded, hairs to 1/4 the length of the lemmas; lemmas 14-22 mm, usually densely strigose below midlength, sometimes sparsely strigose or glabrous, veins not extending beyond the apices, apices usually bifid, teeth 0.3-1.5 mm, awns 23-42 mm, arising in the middle 1/3 of the lemmas; lodicules without lobes on the wings; anthers about 3 mm. 2n = 42.

Distribution

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

Discussion

Avena fatua is native to Europe and central Asia. It is known as a weed in most temperate regions of the world; it is considered a noxious weed in some parts of Canada and the United States.

Avena fatua is sometimes confused with A. occidentalis, but differs in having shorter, wider spikelets, fewer florets, and a distal floret which does not have a heart-shaped disarticulation scar. Hybrids between A. fatua and A. sativa are common in plantings of cultivated oats. The hybrids resemble A. sativa, but differ in having the fatua-type lodicule; some also have a weak awn on the first lemma. They are easily confused with fatuoid forms of A. sativa.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Avena fatua"
membranous +  and scarious +
3 cm30 mm <br />0.03 m <br /> (?) +
Bernard R. Baum +
1 (?) +  and 3 (?) +
straight +
once-geniculate +
2.3 cm23 mm <br />0.023 m <br /> (4.2 cm42 mm <br />0.042 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
10 cm100 mm <br />0.1 m <br /> (45 cm450 mm <br />0.45 m <br />) +
not evident +
scabridulous +
cross +, linear +  and narrowly lanceolate +
3mm;15mm +
spikelike +
rounded +  and pointed +
Wild oats +  and Folle avoine +
not branching +
erect +  and prostrate +
8 cm80 mm <br />0.08 m <br /> (160 cm1,600 mm <br />1.6 m <br />) +
not woody +
Conn. +, N.J. +, N.Y. +, Wash. +, W.Va. +, Del. +, Wis. +, Idaho +, Mont. +, Oreg. +, Wyo. +, Pacific Islands (Hawaii) +, Fla. +, N.H. +, N.Mex. +, Tex. +, La. +, Alta. +, B.C. +, Man. +, N.B. +, Nfld. and Labr. (Labr.) +, N.S. +, N.W.T. +, Ont. +, P.E.I. +, Que. +, Sask. +, Tenn. +, Pa. +, Calif. +, Nev. +, Va. +, Colo. +, Alaska +, Ala. +, Vt. +, Ill. +, Ind. +, Iowa +, Okla. +, Ariz. +, N.Dak. +, Nebr. +, S.Dak. +, Maine +, Md. +, Mass. +, Ohio +, Utah +, Mo. +, Minn. +, Mich. +, Kans. +, Miss. +  and Ky. +
1/4 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
sterile +  and bisexual +
compressed +
reduced +
shorter or longer +
subtending +
subequal +
1.8 cm18 mm <br />0.018 m <br /> (3.2 cm32 mm <br />0.032 m <br />) +
membranous +
0 +  and 1/4 +
uncinate +
lanceolate +  and ovate +
1.4 cm14 mm <br />0.014 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
membranous +
inconspicuous +
not toothed +  and toothed +
concealed +  and prominent +
2 +  and 1 +
entire +  and bifid +
well-developed +
2-keeled +
7cm +  and 40cm +
spikelike +
5 cm50 mm <br />0.05 m <br /> (20 cm200 mm <br />0.2 m <br />) +
dry +  and fleshy +
not disarticulating +
not prolonged +
round +  and ovate or triangular +
15 +  and 50 +
compressed +
1.8 cm18 mm <br />0.018 m <br /> (3.2 cm32 mm <br />0.032 m <br />) +
1 (?) +  and 3 (?) +
simple +  and compound +
2 (?) +  and 3 (?) +
Avena fatua var. glahrescens +  and Avena fatua var. glabrata +
Avena fatua +
species +
membranous +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
parallel +  and converging +
midlength +
glabrous +  and strigose +
stoloniferous +  and rhizomatous +
aquatic +  and terrestrial +