Sitka Alder vs Water Arum

Water Arum is a native perennial wetland plant known for its showy white oval sheaths (spathe) that surround a yellow-green, cylindrical flower spike (spadix). It has large, oblong, heart-shaped leaves on stems that rise above the water from shallow, spreading rhizomes. The blossoms are followed in late summer by tiny, pear-shaped fruits that ripen to bright red, adding ornamental interest to wet habitats.

Water Arum provides food for birds and small mammals that eat its berries, and its flowers attract pollinators. It can tolerate cold climates and forms colonies in shallow water and saturated soils. It is well-suited for ecological restoration, riparian planting, naturalisation, and habitat projects in wet and shaded environments.

Sitka Alder is a native deciduous shrub or small tree that often forms dense thickets. Its extensive root system stabilizes slopes and streambanks. Nitrogen-fixing capabilities and nutrient-rich leaf litter improve soil fertility, creating better growing conditions for surrounding plants. These qualities make it especially effective in disturbed or erosion-prone sites.

Often found in moist, high-elevation mountain environments, Sitka Alder also enhances habitat by providing cover and structure in both riparian and upland areas. Birds and small mammals utilize it for nesting, and its seeds serve as a food source.

Note: We use Sitka Alder for Alnus alnobetula subsp. sinuata. This species is also known by many other common names, including Mountain Alder, Green Alder, and others. Please confirm the scientific name to ensure you are ordering the correct plant.

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