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Alnus oblongifolia - Arizona alder

Scientific Family
Betulaceae
Other common names
oblong leaf alder
Plant type
Trees
Riparian
Yes

Plant Description

Origin
Native

Upright tree with a narrow rounded crown, often with several trunks, reaching 98 feet tall. Bark dark gray to brown, smooth, breaking into shallow vertical plates with age.

Tall spreading crowns. Oval-shaped leaves, prominently veined, shallowly and doubly toothed, tapered at base. Female flower spikes smaller than male. Male flowers have 2 stamens. Fruit has overlapping papery scales giving appearance of small cone.

Height
Up to 98 feet

Habitat

Habitat description

Sandy or rocky stream banks and moist slopes.

Plant Community
Riparian
Low elevation
3200
High elevation
8000

Leaves

Leaf color
Green
Leaf type
Simple
Leaf shape
Round or oval
Leaf margin
Toothed
Leaf attachment
Alternate
Leaf hairs
Bottom of leaves
Spines
No
Leaf Drop
Deciduous

Dark green above and paler green and slightly hairy below. Elliptical shape 3 inches long by 2 inches wide with narrow base and doubly-toothed margins, secondary teeth distinctly larger.

Flowers

Flower color
Yellowish-green or reddish-green
Flower shape
Inconspicuous
Tubular
No
First bloom month
April
Last bloom month
June

Male and female catkins on same tree. Males flowers are yellowish-green, elongated, catkins about 2 to 3 inches long in hanging clusters. Female flowers are very small (1/4 inch) reddish-green. Flowers appear before leaves in early spring.

Flower clusters
Elongated

Fruit

Fruit color
Green to reddish-brown
Fruit type
Cone or cone-like

Cone-like, woody, 1/2 inch long, green but turning reddish-brown when ripe. Contains numerous small winged seeds that ripen in early fall and persist through the winter.

Bark/Branches

Bark color
Dark gray to brown
Bark texture
Rough

Dark gray to brown and smooth with numerous short raised pores when young. Older bark develops rectangular, flat narrow plates that are scaly.