Does anyone know of a subspecies of Ostrya virginiana? I discovered one in northern Michigan that had relatively smooth bark, growing wild at a campground near a lake. It had the readily-identifiable seed cones on it; also, the leaf of Ironwood is easy to get to know -- it feels rather silky compared to elm, for example. Trees I have seen around mid-Michigan have longitudinally shredding bark, as is usually described and shown in photographs, such as here.
I couldn't find anything about subspecies on a cursory search of the usual suspects for eastern North American plants.
The populations on the Atlantic coastal plain are sometimes distinguished as var. or subsp. lasia, with smaller, more pubescent leaves, but this is not widely recognised. For more details, see the Flora of North America account: http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=233500839
What about the possibility of a hybrid? There are not any other native Ostrya, but could it possibly hybridize with another member of the birch family, Carpinus or Alnus, for example?
No hybrids with any other genera. There are other species of Ostrya in Europe and Asia, but they are unlikely to be growing in the situation reported.
No, I am familiar with that tree (Musclewood, Hornbeam, or Blue-beech.) For one, the fruit is significantly different. The nutlet (seed) of Ironwood is within a small inflated pod, while the nutlet of Musclewood is attached to a 3-winged, leaf-like bract; although, these pods or bracts are in pendent clusters on both trees. I wish I had got a picture of the bark and the tree; I'll have to take another trip up there this year.
This tree was probably seven inches in trunk diameter, about 20 feet tall. I was called away before thinking to get a good photograph, because the group I was with was about to depart on an excursion to a local winery. I grabbed one of the hop-like fruit clusters as I left the tree, which left me with a dozen seeds. I thought I would germinate and try to grow a few to see if this was a geographic variant or if the microclimate caused the apparent difference. They are waiting in the fridge for me to find out how to overcome dormancy. I'd like any suggestions, especially for a scarification treatment. I already tried a warm-cold-warm stratification and didn't have success.
