Quercus rubra L.
Common Name: RED OAK
Coefficient of Conservatism: 5
Coefficient of Wetness: 3
Wetness Index: FACU
Physiognomy: Nt Tree

Thrives in rich mesic forests, but also grows on sandy plains with jack pine and on rock outcrops in the Lake Superior region, rather scrubby in the latter situations but can be a magnificent tree on better soils.

Ordinarily, Red Oak can be fairly easily recognized by the shallowly lobed, dull leaves, the lobes broadest at the base and ± tapering (not expanded) distally, the sinuses therefore narrowest at the base and widest at their open end (not narrowed again). The mature leaves are glabrous except usually for small tufts of pubescence persisting in the axils of the main veins beneath (as in Q. velutina), many descriptions of the leaves as completely glabrous notwithstanding. Most of our plants apparently have broad (to 2.5 cm), very flat, saucer-like cups beneath the large acorns and have been referred to var. rubra. Plants with narrower acorns, the cup deeper and often with a suggestion of fringe around the acorn, are var. ambigua (A. Gray) Fernald. Hybridizes with Q. velutina, producing Q. ×hawkinsiae Sudw., collected from Berrien Co. to Oscoda Co. Quercus rubra also hybridizes with Q. imbricaria (see above) and undoubtedly with Q. ellipsoidalis.

Locations

Alcona County
Alger County
Allegan County
Alpena County
Antrim County
Arenac County
Baraga County
Barry County
Bay County
Benzie County
Berrien County
Calhoun County
Cass County
Charlevoix County
    Including Beaver Island
Cheboygan County
Chippewa County
Clare County
Clinton County
Crawford County
Delta County
Dickinson County
Eaton County
Emmet County
Genesee County
Gladwin County
Gogebic County
Grand Traverse County
Gratiot County
Hillsdale County
Houghton County
Huron County
Ingham County
Iosco County
Iron County
Isabella County
Jackson County
Kalamazoo County
Kalkaska County
Kent County
Keweenaw County
    Including Isle Royale
Lake County
Lapeer County
Leelanau County
    Including Fox Islands
    Including Manitou Islands
Lenawee County
Livingston County
Luce County
Mackinac County
    Including Bois Blanc, Mackinac, Round Islands
Manistee County
Marquette County
Mason County
Mecosta County
Menominee County
Midland County
Monroe County
Montcalm County
Montmorency County
Muskegon County
Newaygo County
Oakland County
Oceana County
Ogemaw County
Ontonagon County
Osceola County
Oscoda County
Otsego County
Ottawa County
Presque Isle County
Saginaw County
Schoolcraft County
Shiawassee County
St. Clair County
St. Joseph County
Tuscola County
Van Buren County
Washtenaw County
Wayne County
Wexford County

Citation:

MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. December 18, 2017. http://michiganflora.net/species.aspx?id=1383.