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Carya glabra (Mill.) Sweet
Coefficient of Conservatism: 5
Coefficient of Wetness: 3
Wetness Index: FACU
Physiognomy: Nt Tree

Carya glabra B. S. Walters

Usually in upland, often sandy, forests, associated with oaks. The pignuts are here treated in a broad sense. Some maintain as distinct the red hickory or sweet pignut, C. ovalis (Wang.) Sarg. The distinction can be made with certainty only in the late fall, with fully mature fruit present. The husks split all the way to the base in C. ovalis and only halfway in C. glabra. Unfortunately, even this character, like others, is not fully reliable, for intermediates occur. Carya ovalis, when older, characteristically has “shaggy” or scaly bark, while in C. glabra the bark remains tight and not scaly. There seems to be little correlation among the other characteristics used by various authors. The distribution of the two “species” is essentially the same, but the "ovalis" type is the usual one in Michigan and "glabra" appears to be relatively rare, although many specimens cannot be positively referred to either, in the absence of mature or unambiguous fruit.


Allegan County
Barry County
Berrien County
Branch County
Calhoun County
Cass County
Clinton County
Eaton County
Genesee County
Hillsdale County
Ingham County
Ionia County
Isabella County
Jackson County
Kalamazoo County
Kent County
Lapeer County
Lenawee County
Livingston County
Monroe County
Montcalm County
Oakland County
St. Clair County
St. Joseph County
Van Buren County
Washtenaw County
Wayne County


MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. January 28, 2023.