Northern Prairie Wildlife Research Center


Home	About NPWRC	Our Science	Staff	Employment	Contacts	Common Questions	About the Site

Western Wetland Flora

Field Office Guide to Plant Species

Speckled Alder
Alnus incana (L.) Moench

JPG -- Species Photo JPG -- Distribution Map

Family: Birch (Betulaceae)
Flowering: March-June
Field Marks: This spring-flowering alder is distinguished by having the female flowers borne on drooping branches that are lower than the male flowering branches.
Habitat: Along streams, in swamps.
Habit: Sprawling or upright shrub up to 15 feet tall.
Stems: Trunk and branchlets brown to blackish and marked with elongated, white lenticels.
Leaves: Alternate, simple, ovate to oval to broadly elliptic, rounded to pointed at the tip, rounded or somewhat heart-shaped at the base, usually doubly toothed, more or less smooth.
Flowers: Male and female flowers borne separately but on the same plant, each kind arranged in clusters; male flowers usually 3 in a cluster, subtended by 4-5 small bracts; female flowers in spikes, each pair of flowers subtended by fleshy bracts.
Sepals: 3-5, united, greenish in the male flowers, absent in the female flowers.
Petals: 0.
Stamens: 3-5.
Pistils: Ovary 1, apparently inferior.
Fruits: Woody "cones" up to 1/2 inch long, with narrowly winged nutlets.
Notes: The fleshy bracts subtending the female flowers form the woody scales of the "cone" in fruit. The nutlets are eaten by birds and mammals.

Return to Species List -- Group 5
Next Species -- Thin-leaf Alder (Alnus tenuifolia)

Accessibility FOIA Privacy Policies and Notices

U.S. Department of the Interior | U.S. Geological Survey
URL: http://www.npwrc.usgs.gov/resource/plants/florawe/species/5/alnuinca.htm
Page Contact Information: Webmaster
Page Last Modified: Saturday, 02-Feb-2013 06:25:46 EST
Menlo Park, CA [caww55]