This large, multi-stemmed shrub loves moist soils and sun. It grows 10-15 feet tall and wide in a spreading, pyramidal shape with a densely branched crown. This moisture lover is not picky about soil types, and it tolerates drier soils, flooding, heat, and humidity. It has attractive green leaves that flutter in the breeze, clusters of catkins in the spring, and woody, scaly cones in fall and winter. The tiny, pine-cone-shaped fruits contain winged nutlets that are consumed by birds and small mammals. The cones persist on the shrub for up to a year, joining the early spring catkins and creating an interesting display.
 
This fast-growing plant has a vigorous, suckering root system and the ability to fix nitrogen, so it’s an important plant for restoring wetlands and controlling erosion. As it forms colonies, the surrounding soil improves and becomes more receptive for other plants. When sited near streams, rivers, and ponds, alder shades the water, which helps to protect fish and other wetland species.
 
Native habitats include stream and river banks and swamps, where it acts as a stabilizer. It prefers wetter sites and is well-suited for rain gardens, pond edges and stream banks, mass plantings for erosion control, and naturalized areas. To rejuvenate and tidy its appearance, prune every few years by cutting branches to 6” from the ground.
 
Plant Characteristics:
Grows 10-15’ tall and 8-15’ wide.
 
Prefers full sun; tolerates part shade.
 
Prefers medium-to-wet clay, loam, and sand; tolerates poor soils. May develop chlorosis in alkaline soils.
 
Blooming occurs before leaf emergence from March to April. Slender, brownish-yellow male catkins droop in clusters and short, upright, red female catkins grow on twig tips (alder is self-fertile). Females, which are wind pollinated, develop into 1”- long cones containing winged nutlets, or seeds. Cones mature to dark brown in fall and persist through winter.
 
Broad, flat, elliptical leaves are glossy green and 2-4” long with wavy margins, prominent veins, and pointed tips. Fall color is yellow brown.
 
Multi-stemmed trunk has dense branches and smooth, shiny, gray bark.
 
Wildlife Value:
Alder is a host plant for 188 species of Lepidoptera larvae in central Ohio, including one specialist moth that feeds only on plants in the Alnus family, the Baileya doubledayi (pictured here). It also supports many sawfly larvae and other insect species. Small mammals eat the pollen-rich male catkins in the spring. Hazel alder is a preferred source of food for a variety of songbirds. Pine siskins, goldfinches, sparrows, redpolls, crossbills, and insectivorous birds such as bluebirds, chickadees, and warblers feast on the huge variety of larvae and insects that inhabit this shrub. Alder aphids feed on the leaves in spring, and the adult harvester butterfly--North America’s only carnivorous butterfly--and its carnivorous larvae eat the aphids (pictured second).
 
Medicinal, Edible, and Other Uses:
A tea made from the bark has been used to treat diarrhea, coughs, toothaches, sore mouth, and the pain accompanying labor and childbirth. Alder catkins are high in protein and a bit bitter, so they are used as a survival food. Native Americans ate the inner bark in springtime.
 
The wood is used for making furniture, carvings, and the bodies of electric guitars. The bark is traditionally used to tan leather or to make a beautiful orange dye.