Nov 23 2011
Today is the first entry in this winter’s Wednesday tree series.
Though I mentioned we would identify trees by their twigs I can’t resist starting the series with a tree that’s really easy to identify by its bark.
This is the Northern Hackberry (Celtis occidentalis), a member of the Hemp family. It produces small berries that ripen in autumn. Some berries fall to the ground, others persist on the tree into the winter and provide a good food source for birds.
For me the easiest way to identify young hackberry trees is by their bark. (Bark is at eye level!)
Hackberry bark looks as if someone glued lumpy pie-crust ridges onto the originally smooth gray surface. You can see these odd ridges in the photo above.
A second very distinctive trait is the witch’s broom, easy to see when the leaves are off the trees. Not all hackberries have these bundles of malformed twigs but when you see them in combination with the lumpy bark you can be sure you’ve found a hackberry.
Here’s a close-up of a witch’s broom. Not only do the twigs clump at one spot but there are woody lumps at their base.
As the trees mature the pie-crust lumps grow farther apart and sometimes look as if they’ll peel off the trunk.
Hackberries are easy to find in Schenley Park, especially near the Greenfield Bridge.
(three photos by Kate St. John. Photo labeled UGA5188076 is by Whitney Cranshaw, Colorado State University from Bugwood.org )