Chinkapin Oak (Quercus muehlenbergii)
Chinquapin oak is the #1 species commonly mistaken for Ozark chinquapin. The chinquapin oak has leaves with rounded teeth and buds are clustered at the stem’s apex.
Chinquapin oaks have acorns with a cap unlike Ozark chinquapin which have a nut encased in a prickly burr. Chinquapin oak, chestnut oak, and swamp oak are all common species that resemble OC based on leaf morphology until you look closer.
Chinese chestnuts (Castanea mollissima)
Unfortunately a large number of non-native Chinese chestnuts and hybrid chestnuts have been planted in the Ozarks. If you think you found a tree (Ozark chinquapin), start by looking at the identification guide keeping in mind the location and habitat where you found the tree–this will help you determine if the tree might be another kind of non-native chestnut species or a hybrid.
One of the easiest ways to separate Ozark chinquapin from Chinese chestnut is to very closely examine the edge of leaf:
Chinese chestnut; round edge with pointed hook on the end of each “wave”
Ozark chinquapin bark is quite distinct in that it has flat broad ridges that are arranged parallel to one another. They also have grey colored patches when they are young and as they age :
Chinese chestnut bark with irregular ridges
Chinese chestnuts will grow in many places that Ozark chinquapin will not. Ozark chinquapin have more specific habitat preferences. If you found a tree near an old farm house, in a back yard, public park, or near a University or similar establishment, there is a good chance it is not an Ozark chinquapin.
Promising locations to find a tree: Old growth forest, woods, national forests, natural areas and conservation areas. However, the US Dept. of Agraculure planted hybrid (Chinese x American) chestnuts on national forest lands and various parks in the past. For example: Ouachita National Forest in Polk county Arkansas and Sinkin Experimental Forest in Dent county Missouri.
Finding trees in remote areas that are not easily accessed by people are also usually promising. When you find a natural wild Ozark chinquapin you will almost always find them in a group and not isolated. You will also often see evidence of old blight killed rot-resistant logs on the ground near the tree if the area is not been managed with prescribed burns (or natural fire events destroying the evidence of those logs).
The complete absence of blight symptoms may also indicate that the tree is not of native origin.
When you find a tree, always look around it for burrs. This is another easy way to tell if it is an Ozark chinqaupin is the size of the burr and nut. OC will only have one nut per burr usually.
Ozark chinquapin burrs held in hand for size reference