Aruncus is a genus of clump-forming herbaceous perennial plants in the family Rosaceae, order Rosales. The genus is closely allied to Spiraea, though phylogenetic studies have shown it to be less closely related to Filipendula, which is now placed in the separate subfamily Rosoideae despite a superficial resemblance. Plants are native to mountainous damp woodland in temperate regions of the Northern Hemisphere. Aruncus species are recognised by their tall, arching plumes of creamy white flowers held above foliage of veined and toothed leaflets. The number of accepted species varies by authority — from one to four — with some botanists treating all forms as varieties of the wide-ranging Aruncus dioicus (goatsbeard), while others recognise distinct species such as the Yunnan endemic Aruncus gombalanus and the broadly distributed Asian Aruncus sylvester. The genus is valued in ornamental horticulture for its tolerance of shaded woodland gardens and its dramatic floral plumes in early summer.
Etymology
The genus name Aruncus derives from the Latin word aruncus, meaning "goat's beard," a reference to the long, feathery white flower plumes that resemble a goat's beard. The common name "goatsbeard" is applied to the most widespread member, Aruncus dioicus.
Distribution
Aruncus is native to mountainous damp woodland in temperate regions of the Northern Hemisphere, with the primary species Aruncus dioicus distributed across the cooler parts of Europe, Asia, and North America. Aruncus gombalanus has a more restricted range, confined to the mountains of northwest Yunnan and adjacent Tibet.
Cultivation
Goatsbeard thrives in USDA Plant Hardiness Zones 4–9 in almost any soil type, tolerating full sun to light shade. Plants should be spaced approximately 18–24 inches apart. Clumps can be divided in spring or autumn to propagate new plants, but undisturbed clumps persist indefinitely. Aruncus aethusifolius has received the Royal Horticultural Society's Award of Garden Merit.
