Plant of the Month - January, 2006

ARBORETUM PLANT OF THE MONTH FEATURE
by Jeff Iles
Arboretum Board Member

Professor and Chair
Department of Horticulture
Iowa State University

Acer maximowiczianum
(Nikko Maple)

Like the smallest player on a basketball team, trees that mature at modest heights must bring something "special" to their game if they're to be noticed. And in my opinion, Nikko maple does. What? You've never heard of Nikko maple? Surely you've stood near the waterfall amidst the Heartland Collection of Garden Conifers and cast your gaze westward, allowing your eye to traverse Rock Creek at the northern most Kershner Memorial Crossing. There! It's the tree with the short trunk and decidedly upright branching habit. C'mon, let's hike to the bottom of the hill and I'll introduce you.

Similar to paperbark maple (Acer griseum) and three-flower maple (Acer triflorum), Nikko maple has trifoliate leaves (3 leaflets per leaf). For a brief time after emergence, the foliage has a bronzy hue, but this interesting effect is short-lived and green leaves soon envelope Nikko's vase-shaped frame. When environmental conditions cooperate, fall foliage can be spectacular (reddish-orange), but there's an equal chance muted tones of yellow and red will predominate. And the otherworldly visage of hoarfrost clinging to the twigs and branches of Nikko maple is the perfect tonic for a frigid January morning.

Size (20-30 feet tall and two-thirds as wide), proven pest resistance, and reliable low temperature tolerance in zone 5 (maybe zone 4 in protected sites), qualifies Nikko maple as an excellent specimen tree for smaller residential properties, courtyards, and other intimate spaces. Perhaps, the greatest challenge facing those of you smitten with the understated elegance of Nikko maple and wishing to incorporate one into your own landscape simply will be... finding one at your local garden center. To say they are scarce in the nursery trade would be a gross understatement.

Now, what about that name? The scientific name Acer maximowiczianum (max-im-ō-wix-ē-ā-num) was given to honor Carl Johann Maximowicz (1827-1891), a Russian botanist who earned a reputation as a specialist in Japanese flora. But it was Charles Maries, a horticultural collector from England who between 1877 and 1880 explored the forests of Japan, eventually introducing Acer maximowiczianum to England from the region near the famous shrine city of Nikko, Japan. Nikko maple finally made its way to the United States in 1881.


About the author: Dr. Jeffery Iles presently serves as Professor and Chair of the Department of Horticulture at Iowa State University in Ames, Iowa. He holds advanced degrees from Penn State University and Iowa State University. Among many awards and honors, Dr. Iles is an Honorary Lifetime Member of the Iowa Nursery and Landscape Association. He has authored or co-authored more than twenty journal articles in such journals as HortTechnology, Journal of Environmental Horticulture, Journal of Arboriculture, and HortScience. Research projects Dr. Iles is currently involved in include Landscape Plant Evaluation, Invasive Landscape Plants, and Landscape Plant Usage. The Bickelhaupt Arboretum is fortunate to have Dr. Iles on its Board of Directors.