Moisture-loving trees that thrive in moist or wet soils, even tolerate periodic flooding. Good near creeks and other waterways. Very fast growing. In all species, clusters of tassel-like, greenish yellow male flower catkins give interesting display before leafout. Female flowers develop into small woody cones that decorate bare branches in winter; these delight flower arrangers. Seeds attract birds. Alders need little pruning except to remove suckers, crossing branches, and dead wood.Alnus rhombifolia
Native along streams throughout most of California’s foothills except along the coast; mountains of Oregon, Washington, British Columbia, and Idaho. This fast grower reaches 50–90 ft. tall and 40–60 ft. wide. Branches spread out, then droop at the tips. Coarsely toothed leaves are dark green above and paler green beneath. Tolerates heat and wind. Susceptible to tent caterpillars, borers, and mistletoe in its native range.
Native along streams throughout most of California’s foothills except along the coast; mountains...
Grows to 5–10 in. high and 1 ft. wide. Its erect, unbranched stems are densely clothed with narr...
From the eastern U.S. This is the most widely planted species. Grows to 1–2 ft. high and 1 1/2 f...