text from an article in the March 2001 issue of Castanea (Vol. 66 no. 1), by James R. Allison and Timothy E. Stevens

FOOTNOTE

9. Species with leaves strongly basally disposed, when growing in close proximity, have been observed to hybridize with each other, e.g. S. laciniatum L. X S. terebinthinaceum Jacq. (J. Allison and J. MacDonald 11339, GA, GH, NY, US). Likewise, the several varieties of the leafy-stemmed S. asteriscus seem readily to cross with each other, as well as with S. trifoliatum var. latifolium.