ï~~2005
THE MICHIGAN BOTANIST
111
THE BIG TREES AND SHRUBS OF MICHIGAN
47. Acer negundo L.
Box Elder or Ash-leaf Maple
Elwood B. Ehrle
Department of Biological Sciences
Western Michigan University
Kalamazoo, MI 49008
[email protected]
The largest known Box Elder in Michigan is located in Milan, MI, in Washtenaw County in the southeast portion of Michigan's Lower Peninsula. This is a
State and National Co-Champion tree.
Description of the species: The Box Elder is the only maple in Michigan having pinnately compound, opposite leaves and the characteristic maple samara
fruit (Fig. 1). Box Elders have trunks that frequently branch close to the ground.
The twigs are green and have a waxy bloom. The Box Elder flowers in late April
or early May just as the leaves are becoming obvious. The trees are dioecious.
The samaras are quite distinctive. They are "narrow, flat and in v-shaped pairs"
(Barnes & Wagner, 1981).
Location of Michigan's Big Tree: Milan, MI, is south of Ann Arbor and can
be reached by taking exit 180 (Rt. 23 S ) off 1-94 and heading south to Carpenter St. (exit 27). Carpenter St. becomes Dexter St. in Milan. Continue south on
Dexter St. to the end and turn left onto Main St. The tree is beside the driveway
at 226 Main St., next to a white house with blue trim and a large porch. The coordinates for this location are 42Â~ 04.970' N and 83Â~ 40.710' W.
Description of Michigan's Big Tree: The tree has a healthy, solid, single trunk
to a height of 5'. It then divides into three large branches. The girth was measured at 260" on 23 August 2003 by Gail McPherson of Global ReLeaf of Michigan, Richard Pomorski, noted Ann Arbor area Big Tree hunter, and Elwood B.
Ehrle. The height was 76' and the average crown spread 67'. The total number of
points for this tree (Girth + Height + % of the crown spread) is, therefore, 260 +
76 + of 67 = 353.
There is another very large Box Elder near Milan, MI. It is the former State
and National Champion tree. It can be found at Saline and Mooresville Roads
northwest of Milan. It was measured at G = 214, H = 110, & C.S. = 127. The
total points for this tree (G + H + Y of C.S.) = 356. These two trees are
Co-champions in several ways The tree at Dexter and Main Sts. has a larger
girth, but the tree at Saline and Mooresville Rds. is higher and has a wider
crown.
