Betula populifolia 'Whitespire Senior'
Whitespire Senior Gray Birch
formerly B. platyphylla var. japonica ‘Whitespire’
Native to (or naturalized in) Oregon:
- Deciduous tree, 30-40 ft (10-12 m) tall, upright habit, bark attractive, grayish-white with black markings, leaves glossy green, yellow in fall.
- Sun, will grow on poor soil, both wet and dry. Shows some resistant to bronze birch borer.
- Hardy to USDA Zone 4
- The Whitespire Story: It was selected and introduced, in 1983, by Edward R. Hasselkus, University of Wisconsin-Madison and named Betula platyphylla var. japonica ‘Whitespire’, Whitespire Asian White Birch. Later it was realized that there had been an error in record keeping and that ‘Whitespire’ was a Gray Birch (Betula populifolia), not a selection of Asian White Birch, and it did not originate from birch seeds collected by John L. Creech in Japan in 1951 as had been reported. Around 1993 this selection was renamed Betula populifolia ‘Whitespire’, unfortunately some nurseries still offer it as Whitespire Asian White Birch even when they have adopted the correct scientific name. The cultivar name Whitespire was applied to a vegetatively propagated clone of the original Wisconsin tree, this tree had not succumbed to bronze birch borer whereas many of the surrounding birch trees at this site had. As of 2006, the original ‘Whitespire’ tree, then 49 years old, was still free of bronze birch borer (Ed Hasselkus, personal communication). Unfortunately, the name Whitespire has also been applied to seed propagated material, i.e., to trees not genetically identical to the original tree. To emphasize this important difference, the cultivar name ‘Whitespire Senior’ is now used to designate clonal material from the original tree and ‘Whitespire Junior’ for the seed propagated trees.
- populifolia: popular-leaved.