Alnus oblongifolia

Torrey in W. H. Emory

in W. H. Emory, Rep. U.S. Mex. Bound. 2: 204. 1859.

Common names: Arizona alder New Mexican alder aliso (Mexico)
Treatment appears in FNA Volume 3.

Trees, to 30 m; trunks often several, crowns spreading. Bark dark gray, smooth, becoming blackish and breaking into shallow vertical plates in age; lenticels inconspicuous. Winter buds stipitate, ovoid, 4–8 mm, apex rounded; stalks 1.5–4 mm; scales 2, equal, valvate, sometimes incompletely covering underlying leaves, moderately resin-coated. Leaf-blade narrowly ovate or lanceolate to narrowly elliptic, 5–9 × 3–6 cm, leathery, base narrowly to broadly cuneate or narrowly rounded, margins flat, sharply and coarsely doubly serrate, rarely evenly and densely short-serrate, major teeth sharp, acuminate, secondary teeth distinctly larger, apex long to short-acuminate, rarely acute; surfaces abaxially glabrous to sparsely pubescent or infrequently villous, moderately resin-coated. Inflorescences formed season before flowering and exposed during winter; staminate catkins in 1 or more clusters of 3–6, 3.5–10 cm; pistillate catkins in 1 or more clusters of 2–7. Flowering before new growth in spring. Infructescences ovoid, ellipsoid, or nearly cylindric, 1–2.5 × 0.8–1.5 cm; peduncles 5–10 mm. Samaras elliptic to obovate, wings narrower than body, irregular in shape, leathery.


Phenology: Flowering early spring.
Habitat: Sandy or rocky stream banks and moist slopes, often in mountain canyons
Elevation: 1000–2300 m

Distribution

V3 1070-distribution-map.gif

Ariz., N.Mex., Mexico (n Chihuahua and n Sonora)

Discussion

Alnus oblongifolia is closely related to the Mexican and Central American A. acuminata, with which it has sometimes been confused. It is found only in scattered populations in the temperate deciduous forest vegetation zone of high mountains in the arid Southwest.

Selected References

None.

Lower Taxa

None.

"persistent" is not a number.

... more about "Alnus oblongifolia"
John J. Furlow +
Torrey in W. H. Emory +
tanniferous +  and furrowed +
blackish +  and dark gray +
exfoliating +
rounded +  and cuneate +
2 (?) +  and 3 (?) +
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
pistillate +  and staminate +
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 +
3.5 cm35 mm <br />0.035 m <br /> (10 cm100 mm <br />0.1 m <br />) +
Arizona alder +, New Mexican alder +  and aliso (Mexico) +
multibracteate +
Ariz. +, N.Mex. +  and Mexico (n Chihuahua and n Sonora) +
1000–2300 m +
pistillate +  and staminate +
reduced +  and small +
small +  and large +
Sandy or rocky stream banks and moist slopes, often in mountain canyons +
1 cm10 mm <br />0.01 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
cylindric +, ellipsoid +  and ovoid +
1 cm10 mm <br />0.01 m <br /> (4 cm40 mm <br />0.04 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
membranaceous +  and leathery +
5 cm50 mm <br />0.05 m <br /> (9 cm90 mm <br />0.09 m <br />) +
3 cm30 mm <br />0.03 m <br /> (6 cm60 mm <br />0.06 m <br />) +
3-ranked +  and nearly 2-ranked +
inconspicuous +
short-serrate +  and serrate +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
not obvious +  and defined +
membranaceous +
Flowering early spring. +
2(-3)-carpellate +
shallow +
in W. H. Emory, Rep. U.S. Mex. Bound. +
1-seeded +  and 2-winged +
elliptic;obovate +
crowded +  and imbricate +
resin-coated +
deciduous +  and persistent +
expanding +
thicker +  and thin +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
nearly +  and distinct +
resin-coated +
abaxially glabrous;sparsely pubescent or infrequently villous +
Alnus oblongifolia +
species +
acuminate +  and sharp +
excurrent +  and deliquescent +
differentiated +  and uniform +
irregular +
leathery +
narrower +
tanniferous +
light +  and white +