72 Microseasons of the Pacific Northwest

Red elderberry (Sambucus racemosa) is among the most structurally important shrubs in Pacific Northwest forest ecosystems, and its bloom in mid-May marks a key transition as the season moves from early spring wildflowers to the leafed-out green of early summer. The conical to egg-shaped panicles of tiny creamy-white flowers erupt at branch tips, often visible from a distance against the darker greens of the surrounding forest. The blooms carry a faint sweet fragrance that draws in native bees, hoverflies, and butterflies in large numbers. The shrub is found region-wide from the coast to mid-elevation slopes in the Cascades and Olympics, typically colonizing stream banks, forest clearings, avalanche chutes, and roadsides. In Olympic National Park, it is a characteristic plant of the Hoh and Quinault rainforest margins. Along Highway 20 through the North Cascades, elderberry forms dense thickets at lower elevations. On southern Vancouver Island and the Gulf Islands, it is a conspicuous early bloomer in hedgerows and along estuary margins. The ecological value of the bloom extends well beyond pollinating insects. Anna's hummingbirds, which are resident year-round in the lowlands, visit the flowers for nectar in May. Warblers, vireos, and flycatchers forage through the flower clusters for insects attracted to the bloom. By midsummer, the flower clusters will mature into the bright red berries that make red elderberry one of the most important food shrubs for cedar waxwings, American robins, Swainson's thrushes, and ruffed grouse. In May, however, the white flowers against a green backdrop give streamside trails and forest roads a distinctly festive quality that is hard to overlook.