Alnus incana

(Linnaeus) Moench

Methodus, 424. 1794.

Basionym: Betula alnus var. (ß) Linnaeus Sp. Pl. 2: 983. 1753
Treatment appears in FNA Volume 3.

Trees and shrubs, to 25 m; crowns open. Bark light to dark gray, reddish, or brown, smooth, or in age broken into irregular plates; lenticels present or absent, conspicuous, enlarged or unexpanded. Winter buds stipitate, ellipsoid, 4–7 mm, apex rounded to nearly acute; stalk 1–3 mm; scales 2–3, equal, valvate, resin-coated. Leaf-blade narrowly ovate to elliptic, base cuneate to narrowly rounded, margins doubly serrate, with distinctly larger secondary teeth, apex acute or short-acuminate to obtuse. Inflorescences formed season before flowering and exposed during winter. Flowering before new growth in spring. Infructescences ovoid to nearly cylindric; peduncles relatively short and stout. Samaras elliptic to obovate, wings narrower than body, irregular in shape.

Distribution

Alta., B.C., Man., N.B., N.S., N.W.T., Nfld. and Labr. (Nfld.), Ont., P.E.I., Que., Sask., Yukon, Alaska, Ariz., Calif., Colo., Conn., Idaho, Ill., Ind., Iowa, Maine, Mass., Md., Mich., Minn., Mont., N.Dak., N.H., N.J., N.Mex., N.Y., Nev., Ohio, Oreg., Pa., R.I., Utah, Va., Vt., W.Va., Wash., Wis., Wyo., Canada

Discussion

Subspecies 4 (2 in the flora).

Native Americans used Alnus incana medicinally to treat anemia, as an emetic, a compress or wash for sore eyes, and a diaphoretic, for internal bleeding, urinary problems, sprains, bruises or backaches, itches, flux, and piles, to cure saddle gall in horses, and when mixed with powdered bumblebees, as an aid for difficult labor (D. E. Moerman 1986).

Selected References

None.

Key

1 Leaf blade thick, major teeth sharp; large shrubs of ne United States and e Canada. Alnus incana subsp. rugosa
1 Leaf blade thin and papery, secondary teeth rounded or blunt; large shrubs or small trees of w United States, Canada. Alnus incana subsp. tenuifolia

"thin" is not a number."persistent" is not a number.

... more about "Alnus incana"
John J. Furlow +
(Linnaeus) Moench +
tanniferous +  and furrowed +
light +  and dark gray reddish or brown +
exfoliating +
cuneate +  and narrowly rounded +
Betula alnus var. (ß) +
2 (?) +  and 3 (?) +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
staminate +  and pistillate +
in relatively small racemose clusters +  and solitary +
solitary +, cluster +  and racemose +
erect +  and nearly pendulous +
proximal +  and lateral +
enclosed in buds +  and exposed +
ovoid +  and ellipsoid +
expanding +
multibracteate +
Alta. +, B.C. +, Man. +, N.B. +, N.S. +, N.W.T. +, Nfld. and Labr. (Nfld.) +, Ont. +, P.E.I. +, Que. +, Sask. +, Yukon +, Alaska +, Ariz. +, Calif. +, Colo. +, Conn. +, Idaho +, Ill. +, Ind. +, Iowa +, Maine +, Mass. +, Md. +, Mich. +, Minn. +, Mont. +, N.Dak. +, N.H. +, N.J. +, N.Mex. +, N.Y. +, Nev. +, Ohio +, Oreg. +, Pa. +, R.I. +, Utah +, Va. +, Vt. +, W.Va. +, Wash. +, Wis. +, Wyo. +  and Canada +
pistillate +  and staminate +
reduced +  and small +
small +  and large +
ovoid +  and nearly cylindric +
1 cm10 mm <br />0.01 m <br /> (4 cm40 mm <br />0.04 m <br />) +
membranaceous +  and leathery +
3-ranked +  and nearly 2-ranked +
unexpanded +  and enlarged +
not obvious +  and defined +
membranaceous +
2(-3)-carpellate +
1-seeded +  and 2-winged +
elliptic;obovate +
crowded +  and imbricate +
resin-coated +
deciduous +  and persistent +
2 +  and 3 +
expanding +
thicker +  and thin +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
nearly +  and distinct +
glabrous;tomentose +
Alnus incana +
species +
excurrent +  and deliquescent +
differentiated +  and uniform +
shrub +  and tree +
irregular +
narrower +
tanniferous +
light +  and white +