Autumn really is a wonderful time of year for tree watching. Not just for the aesthetic pleasure of seeing various trees' leaves change from green to yellow, orange or red, but also because while this change is taking place, different trees will begin to reveal themselves to you.
For instance, the entry to Central Park near the 5th Avenue stop on the NR train has never slowed my pace very much. If I enter the park here, I usually rush down to the nearby pond (the one where we saw our friend taking a dip last August) and then begin to meander through the landscape.
But on Saturday, this yellow tree caught my eye before I'd even entered the park.
When I neared the tree I quickly realized it was yellowwood (or Cladrastis kentukea, or C. lutea). I was delighted. I love this tree, but until now I have only been able to show students a smallish specimen near the magnolias behind the Met, or the larger one in Jefferson Market Garden.
Yellowwood are fairly easy to identify. They have a pinnately compound leaf with leaflets quite larger than a honey locust, sophora or black locust. More specifically, the terminal leaflet is always broader in shape than the lateral leaflets. It is almost spatula-shaped, where the lateral ones are simple footballs.
Like those other trees with pinnately compound leaves, Cladrastis is in the Fabaceae or pea family (also considered the Leguminosae family). And, like other members of that family, the tree has long, pendulous sweetpea-like flowers in the late spring.
The bark is gray and smooth. If one were to trim a branch and look at the cut, they would see yellow heartwood, thus the common name.
Cladrastis comes from the Greek words klados (branch) and thraustos (fragile). clearly refers to a native range. The other species name, lutea, means yellow.