Acer cissifolium subsp. henryi
Native to (or naturalized in) Oregon:
- Broadleaf deciduous tree or large shrub, to 30 ft tall and wide (~10 m × 10 m), shoots slightly tomentose and brownish green and then darker when mature; new growth reddish. Leaves opposite, compound (trifoliate) 3 elliptic leaflets, each 5-10 cm long, margin serrate or entire, bluish green to olive green above; petiole about 10 cm long. Juvenile leaves coarsely serrate, similar to those of A. cissifolium (van Gelderen and van Gelderen, 1999). "Fall color varies from a good red or adequate pastel mix including red, to simply dreadful" (Jacobson, 1996, p. 16). Flowers in slender whitish-yellow spikes; dioecious - male and female plants. Fruit (samaras) in long drooping clusters, each fruit 2 cm long, wings upright or slightly spreading, nutlets thick and often sterile.
- Sun or shade.
- Hardy to USDA Zone (5) 6 Dirr (1998, p. 17) states that A. henryi survived a winter temperature of -24o F without injury, whereas A. cissifolium was killed to the main trunk. However, van Gelderen and van Gelderen (1999) list Zone 6 as the lowest hardiness zone for A. henryi but Zone 5 for A. cissifolium. Native to central China, mostly in Hubei and Sichuan Provinces.
- Not often in cultivation, some (most?) plants labeled as A. henryi are actually A. cissifolium (van Gelderen and van Gelderen, 1999). According to Jacobson (1996) A. henryi differs from A. cissifolium in that its leaflets are comparatively little toothed or entire, at least on older specimens. Le Hardy de Beaulieu (2003) states that A. henryi is distinguished from A. cissifolium by its red young shoots. But van Gelderen and van Geldern (p. 173) state that "Acer henryi...lacks the conspicuous yellowish orange color in the young growth, which is so attractive in A. cissifolium.
- henryi: after Augustine Henry (1857-1930), who discovered it. For a time he served as a doctor in China during which he collected botanical specimens which he send back home to Ireland. Later he changed careers, studying forestry in France, and was joint author, with Henry Elwes, of the famous seven-volume The Trees of Great Britain and Ireland (1907-1913).
- Oregon State Univ. campus: west side of Weniger Hall, near curb.