A low shrub or small tree of wet ground. A pioneer plant, and one of the first pollen sources for bees in the spring, often before snow melts. Male and female flowers occur on the same plant and male catkins produce large quantities of pollen, often hundreds of pounds per acre, which bees readily collect. When a plant, such as alder, receives no benefit from bee pollination the bees are actually predators as they collect the pollen before it can be released. An easy way to tell this alder from other species is Alnus rugosa has distinct white lenticels on the stems, giving it a speckled appearance, (hence the name).
Flower Color: Male flowers are greenish catkins that turn brown. Female flowers are small 1/4″ cones. Pollen is gray-green on the bee.
Zones: 4 to 10
Growth Habit: Fast
Light needs: Sun to part shade
Flowering season: Early Spring
Landscape Value: 2 of 5. Excellent plants along streams or in poor soils.
Naturalizing Value: 5 of 5
Pollen Value: 4 of 5
Nectar Value: 0 of 5
Water Requirements: Prefers wet feet, but will grow upland.