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 coast; mountains of Oregon, Washington, British Columbia, and Idaho. This fast grower reaches 50–90 ft. tall and 40–60 ft. wide. Branchesspread out, then droop at thetips. Coarsely toothed leavesare dark green above, palergreen beneath. Tolerates heatand wind. Susceptible to tentcaterpillars, borers, and mistletoe in its native range.
Native along streams throughout most of California’s foothills except along coast; mountains of Oregon...
From eastern U.S. Most widely planted species. To 1–2 ft. high and 1 1/2 ft. wide, with 1-in. flowers....
Native from central SierraNevada to British Columbia. To1–3 ft. high and wide. Ovate toelliptical, dar...