Physocarpus monogynus is an upper elevation woody shrub found in moist mixed conifer forest. On first glance, the leaves look like a Ribes-- small, lobed and crenate. However, the peeling bark and fruit are much different. When in bloom Physocarpus monogynus explodes in umbels of white flowers.

Common Name: mountain ninebark

Duration: Perennial

Nativity: Native

Lifeform: Shrub

Wetland Status: UPL

General: Small shrubs with exfoliating bark that comes off in strips, to 1 m tall, much branched.

Leaves: Palmately lobed with 3-5 lobes and divided margins of rounded teeth, doubly crenate, thin, dark green on top and lighter in color underneath, 0.5-3 cm long, 0.5-3 cm wide, cordate base, glabrate or glabrous on both sides to stellate-hairy, especially below.

Flowers: White flowers in roundish terminal corymbs with 9-25 flowers, hypanthium stellate hairy, sepals ovate 2-3 mm long, the 5 petals 2-4 mm long, 2.5-3.5 mm wide, white with many stamens, each stamen topped by a pink, magenta, or white anther, stamens protruding above the top of the flower, pistils 1-5.

Fruits: Small, inflated capsules, dehiscent on both sutures, generally presenting in paired clusters.

Ecology: Found in high-elevation pine and spruce forests from 8,000-9,500 ft (2438-2896 m); flowers June-July.

Distribution: Ranges from the northern plains through the intermountain west south to Arizona and east to Texas.

Notes: The doubly crenate leaves appear at first glance to be Rubus but pay attention to the way the five white petals come off the hypanthium and how at that junction there many fewer stamens in this species, most of all pay attention to the plant being unarmed.

Ethnobotany: Unknown

Etymology: Physocarpus comes from the Greek phusa or physa, bladder, a pair of bellows and karpos, fruit, thus bladdery fruit.

Synonyms: None

Editor: LCrumbacher and SBuckley 2011