Home Forum Resources Shop Journey Log Back to map


Lewis and Clark
SHOWING RECORD: 11 of 23   Sitka Alder
PreviousNextJournals and Maps
image: Sitka Alder
Photograph by Raymond Gehman/Corbis
Sitka Alder
(Mountain Alder)

Alnus sinuata

First Noted by Expedition
September, 1805, on the Lolo Trail, Idaho.

Thicket-forming shrub or small tree, often with several trunks, and with shiny yellow-green leaves, gummy when young. Height: 30 ft (9 m). Diameter: 8 in (20 cm).

Along streams and lakes and in valleys.

Southwestern and central Alaska and Yukon southeast to northwestern California and central Montana; in Alaska to alpine zone above timberline; in northwestern California to 7,000 ft (2,134 m).

Adapted to soils too barren for other trees, this subspecies improves soil conditions by adding organic matter and nitrogen from bacteria in its root nodules.

Species information from enature.com

Subscribe Online
Your subscriptions help National Geographic conservation efforts worldwide >>

Blue Catfish
Franklin's Spruce Grouse
Oregon Ruffed Grouse
Steller's Jay
Common Snowberry
Dwarf Mountain Fleabane
Engelmann's Spruce
Lodgepole Pine
Pacific Yew
Ponderosa Pine
Sitka Alder