General Description

This irregular shrub has been placed on the IUCN Red List as least concern. It is one of few shrubs found in the Betulaceae family.

Landscape

It could be used as a specimen plant due to its unusual leaf-shape.

Cultivation

Prefers moist acidic soil. Can be grown in full sun to partial shade. Tolerant of cold winter temperatures.

Growth

Fast

ID Characteristic

Betula pumila can be distinguished from other shrubs in the genus by its highly pinnate venation in the leaves.

Pests

Vulnerable to canker, dieback, leaf blister, leaf spot and powdery mildew.

Habitat

Low-lying marshes, swamps and lake shores.

Bark/Stem Description

Dark brown colour with a reddish colour at the terminal ends of branches.

Flower/Leaf Bud Description

Buds appear in late winter and are a source of winter food for birds and deer.

Leaf Description

Small, obovate shape with serrate edges (2-3 cm long and 1-2 cm wide). They appear alternately in a simple arrangement and have a pinnate venation pattern.

Flower Description

Cylindric and erect infructescences, 0.8-1.5 x 0.5-1 cm, producing fruit in autumn.

Fruit Description

Female catkins develop ovoid shaped nutlets in groups of 3 with the central scale being slightly larger than the latereal ones.

Colour Description

The leaves are a mild green colour and turn to light yellow in autumn. Catkins are light to moderate green and turn to light brown at maturity. Bark is dark brown and are reddish-brown at the tip of the branch.

Texture Description

Medium texture. Branch and petiole texture ranges from glabrous to pubescent. Leaves are completely glabrous.

Notable Specimens

The University of Guelph Arboretum located East of the university campus in Guelph, Ontario.

Propagation

Propagates through seeds. Must be planted in late autumn to stratify for at least 3 months during the winter. Seeds are to be planted before full maturity is reached (when they will turn from pale green to light brown). Seeds are dispersed broadly with very little covering and can even be sown atop snow. Moisture is more important than low temperature and seeds must be kept moist in order to germinate. Seeds must be kept at 1-3% moisture and at a temperature of 2-5°C if stored.

Ethnobotanical Uses (Disclaimer)

Native American cultures used a solution derived from Betula pumila flowers as a gynecological aid for recovery post-childbirth. The flowers were also burned and inhaled as a respiratory aid to treat build up of mucous by Ojibwe tribes. Small woody branches were used as ribbing in Native basket weaving.

Dirr, Michael, A. (2009). Manual of Woody Landscape Plants. (6th ed.) Illinois: Stipes Publishing L.L.C. Hillier, Edwin. (1973). Hillier’s Manual of Trees and Shrubs. (1st ed.) New Jersey: A.S. Barnes & co., Inc.