A highly toxic plant is flourishing beside the path that goes around Melville Pond, and within reach of any child or adult. Amazing! The striped stem is typical. This plant should be removed post haste! Water Hemlock Another site Note: There is a chance that this is Water Parsnip (not poisonous), but better safe than sorry.
Not to be confused with the American Chestnut (Castanea dentata)which was devastated by the chestnut blight. Spanish Chestnut is also called Sweet Chestnut or European Chestnut. I found this healthy specimen at the edge of a parking lot on the SUNY campus.
The serrations on the leaves are more jagged on the Spanish than on the American chestnut.