Thursday, October 18, 2012

Leaf Spotting

"Leaf Spotting," it all sounds rather English, doesn't it? And while sorting tree species by fall color, I happened onto some very good information in the Hocking Hills.

The peach-hued glow of a Sourwood tree, Oxydendrum arboreum

Travel can expand the mind, and a recent trip to Laurelville, Ohio offered an opportunity to learn from Paul Knoop- the naturalist's naturalist.  He is a legend throughout Ohio.

Serrated leaf edge on Sourwood
We soon focused on the lovely shape, form and fall color of the Sourwood trees.  Being a more Southern species,  its unique serrated edges of the leaf were unknown to me.  It is an excellent key to aid in identification of this tree.

A similar, yet "spotted" leaf, with no edge serration.
Another understory tree begged to be identified, and we were leaning towards calling it a Black-gum / Tupelo.  There were no serrated edges on the leaves.  The bark and leaf shape were right, but these spots on the leaves finally pointed us in the correct direction.

There is only one tree with those diagnostic fall leaf spots: Common Persimmon, Diaspyros virginiana.  It probably did not  get enough sun in this woodland situation to produce fruit.


Common Persimmon leaves

Look for the persimmon's distinctive fall leaves, as seen in the Sibley guide.  Those spots tell the story even when the fruit is not present!  This is another southern Ohio species seen in Hocking Hills and in Shawnee Forest, but not found on my home turf.

It is always good to enjoy the unique qualities of trees.

Add caption
Sibley's Guide to the Trees  has quickly become a favorite guide for many naturalists.

It is a mistake to try to rely strictly on leaves for tree identification, focus more on tree shape, habitat, leaf buds and bark.  The more one studies trees in the winter, the sooner you will realize there are many tip and tricks for identifying trees to species.  

Sometimes, it come down to spots.

No comments:

Post a Comment