Flora of New Zealand Series

western balsam poplar

Large tree, almost pyramidal when young, suckering moderately. Bark grey, fissured, peeling when young. Shoots somewhat angled, brown. Buds and very young shoots very viscid and balsam-scented, glabrous. Petioles to c. 9 cm long, terete, glabrous. Lamina to 13-(18) × 10 cm, usually deltoid-ovate or ovate, sometimes narrow-ovate, greenish white below, glabrous except for ciliolate margin, ± green when very young; veins green above; margin without translucent band, crenate-serrulate; base broad-cuneate, truncate or subcordate, usually glandless; apex acute to short-acuminate. Catkins ♂, pendulous, to c. 10 cm long. Rachis ± puberulent. Bracts 3-4 mm long excluding filiform teeth, hairy, whitish. cup-shaped disc 2-3 mm deep, oblique, glabrous. Stamens 30-90; anthers crimson.

S.: Christchurch.

N. America 1988

Riverbanks.

FL Sep.

Western balsam poplar has been planted in a number of localities in both main islands; trees produce suckers at some distance from the parent and these sometimes appear to be completely spontaneous, especially after the original tree dies. All wild plants in N.Z. are ♂ and represent one clone. Superficially, P. trichocarpa in N.Z. resembles P. × gileadensis, but the latter is a ♀ clone, suckers much more extensively, and has hairy petioles.