Alnus rhombifolia (White Alder)

Fast-growing, Alnus rhombifolia (White Alder) is a medium-sized deciduous tree of graceful habit with a straight trunk, and a pyramidal crown in youth, becoming more oval with age. The slender, horizontal branches spread out, then droop at the tips. The ash gray bark is thin and smooth on young trees, becoming scaly on mature trees. The foliage of broadly ovate, finely toothed leaves, 4 in. long (10 cm), emerges apple green before turning glossy dark green. The leaves appear just after the springtime display of the 6 in. long (10 cm), greenish-yellow catkin. Dangling near the bare branch tips, the catkins are followed by brown, cone-like fruits which persist on the tree throughout most of the year for a unique and lovely display – to the delight of birds. They are also quite popular for use in dried flower arrangements. Native to western North America, White Alder grows along permanent streams and adjacent slopes, in sand, gravel, and other alluvial soils. The roots of mature White Alders can withstand inundation by most large stream flows, making this tree a good choice for planting near creeks, ponds and streams. White Alder is also used for wildfire rehabilitation, riparian restoration, and to stabilize streambanks. Its nitrogen-fixing ability improves soil fertility. Frequently used in urban and suburban landscapes, this heat-tolerant, moisture-loving tree creates a lovely specimen during the winter with a straight trunk, persistent fruits, attractive silver bark, and slender, horizontal branches with pendulous tips. A good An intermediate source of food for wildlife, Alders support 255 species of caterpillars as well as many sawfly larvae. This allows a grove of Alder to provide food and shelter for wintering birds, breeding birds, and migrant birds.

• Grows up to 50-80 ft. tall (15-24 m) and 40-60 ft. wide (12-18 m).
• Performs best in full sun to part shade in moderately fertile, moist, well-drained soils and will happily tolerate the wettest conditions.
• Keep an eye out for borers, tent caterpillars and mistletoe.
• Requires minimal pruning. Any necessary pruning should be done in winter or early spring.
• Propagate by seed or softwood cuttings.
• Native to western North America, from British Columbia and Washington east to western Montana, southeast to the Sierra Nevada, and south through the Peninsular Ranges and Colorado Desert oases in Southern California.