An investigation of Hamamelis vernalis Sarg. and H. Virginiana L. was begun in southwestern Arkansas in the tall of 1976. An overlap of flowering periods occurred from late November through December, affording the possibility of hybridization. At one site the two taxa flowered simultaneously only 30 yards apart. Variation occurs in both taxa and there is a degree of overlap in most characters, but the composite of diagnostic features distinguishes the two species. The hybrid origin of H. vernalis suggested by Jenne (1966) does not seem likely.
Bradford, Jack L. and Marsh, Daniel L.
"Comparative Studies of the Witch Hazels Hamamelis virginiana and H. vernalis,"
Journal of the Arkansas Academy of Science: Vol. 31
, Article 10.
Available at: http://scholarworks.uark.edu/jaas/vol31/iss1/10