Alnus incana ssp. rugosa (Speckled alder)

Alnus incana (L.) Moench ssp. rugosa (Du Roi) R.T. Clausen

Speckled alder, tag alder, hoary alder, gray alder

Kingdom	Plantae	Plants, but not fungi, lichens, or algae
Subkingdom	Tracheobionta	Vascular plants—plants with a “circulatory system” for delivering water and nutrients
Division	Magnoliophyta	Flowering plants, also known as angiosperms
Class	Magnoliopsida	Dicotyledons—plants with two initial seed leaves
Subclass	Rosidae	Roses, legumes, proteas, dogwoods, hydrangeas, mistletoes, euphorbias, grapes, many more
Order	Fagales	Birch, she-oak, beech, walnut, bayberry, others
Family	Betulaceae	Birch family: birches, alders, hazels, hornbeams and hop-hornbeams
Genus	Alnus	The classical Latin name for this genus
Species	incana
ssp.	rugosa

About plant names...

Alders are small to medium in size, often with multiple trunks and branches. Speckled alders grow to 12-36' (3.7-10 m), rarely reaching 60' (18 m), usually less than 20' (6.1 m) tall. These fast-growing trees are often found beside wet areas. The subspecies name, rugosa, means “wrinkled,” and refers to the network of sunken veins on the bottom surface of each leaf. Alder roots, like many legumes, are capable of converting atmospheric nitrogen into usable nutrients, allowing them to grow in relatively infertile soil. These densely branched shrubs, with their penchant for growing in muddy soil and rapid spread by creating clonal colonies, form nearly impassable thickets.

Identification: These alders may be multiply branched large shrubs or small trees.”Speckled” refers to the presence of many lenticels—white, or light gray or orange oval patches, wider than they are flat, on the trunk. Leaves are dark green, alternate, roughly oval, 2-4" (5-10 cm) long, and doubly serrated. Male flowers are catkins 1½-3½" (3.8-8.9 cm) long. Female flowers are cylindrical catkins attached directly to the branch, ⅛" (4.8 mm) long. The fruits are egg-shaped cones about ⅝" (1.6 cm) × ¼" (7.9 mm), green at first, becoming dark brown and often persisting through the winter.

Online References:

Alnus incana ssp. rugosa on Earl J.S. Rook's Flora, Fauna, Earth, and Sky ... The Natural History of the Northwoods

Alnus incana ssp. rugosa at the Virginia Tech Department of Forest Resources and Environmental Conservation

Alnus incana ssp. rugosa on

Alnus incana ssp. rugosa at the Lady Bird Johnson Wildflower Center

8/1/2009 · Stan & Connie’s, Falmouth, Maine
≈ 8 × 7" (19 × 17 cm) ID is uncertain

Alnus incana (L.) Moench var. americana Regel

Alnus rugosa (Du Roi) Spreng.

Alnus rugosa (Du Roi) Spreng. var. americana (Regel) Fernald

Alnus incana ssp. rugosa description by Thomas H. Kent, last updated 25 May 2020.

10/17/2011 · Nashua River Rail Trail, Groton Center, Groton, Massachusetts
≈ 5 × 4½" (13 × 11 cm) ID is uncertain

10/16/2011 · Nashua River Rail Trail, Groton Center, Groton, Massachusetts
≈ 5 × 3½" (12 × 9.4 cm) ID is uncertain

10/16/2011 · Nashua River Rail Trail, Groton Center, Groton, Massachusetts
≈ 3½ × 3" (9.3 × 8.4 cm) ID is uncertain

8/1/2009 · Stan & Connie’s, Falmouth, Maine
≈ 4½ × 3½" (11 × 9.5 cm) ID is uncertain

Range:

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