Plant of the Week
Big-leaf witch-hazel (Hamamelis ovalis S.W. Leonard). Flower South Mississippi. Photo by Steve Leonard.
Big-leaf witch-hazel (Hamamelis ovalis)
By Ken L. Gordon, Botanist, National Forests in Mississippi
Big-leaf witch-hazel is a species worthy of note for several reasons. First, it is a newly described (new to science) woody shrub from the southeastern states where conventional wisdom had decreed there were no new species to be discovered. Second, it is known only from a very small area in the headwaters of one creek in southern Mississippi. The new species was first noticed in July 2004 when Steve Leonard was conducting botanical surveys on Camp Shelby training site. Leaves two to three times larger than the common eastern witch-hazel caught Steve’s attention when he first saw these plants. His first impression of the leaves was how much they resembled hazelnut leaves in shape. The lower leaf surfaces were soft, and on new leaves, densely white. Closer examination of the plants revealed the clonal nature of the shrubs where a few plants were 4-8 feet tall but the majority was only 1-2 feet. tall. The short runners are shallowly rooted and easy to pull up. In contrast, the other two USA species are deeply and securely rooted. When he returned in early January to view the flowers, another surprise awaited. The flowers were of various shades of red! The colonies tend to have one dominant “red” form with a few bushes of variants. The dominant forms may be scarlet, rose-pink, wine-red, or maroon. Usually the colony will have a few shrubs that show some yellow influence where the petals are bicolored. The combination of leaf and flower appearance coupled with the clone-forming habit of the plants did not match any known species of witch-hazel and convinced Steve to embark on a voyage of discovery that led to the final conclusion that big-leaf witch-hazel was indeed a new species!
The known distribution of this species is extraordinarily small, part of one county. Big-leaf witch-hazel grows in shallow flat-bottomed ravines and on adjacent low slopes. Soil is loamy in texture. The shrub occurs beneath a canopy of pine and mixed deciduous hardwoods. The species apparently tolerates prescribed burning which is typical management in the longleaf pine woods of south Mississippi.
One interesting theory proposed by Steve Leonard was that the new species might represent a rediscovery of the “lost” species Hamamelis macrophylla that was discovered and offered for sale in 1812 by John Lyon, a Scottish nurseryman who worked out of Philadelphia and made commercial collecting trips as far south as Georgia and Florida. The locality from which Lyon collected his plant is very vague. The site could be from a river bank in the western Georgia or the “Katawba (sic) mountains in western North Carolina. Since none of his specimens are known to survive and his description of the locality was brief to the point of confusion, this theory remains an intriguing mystery. Perhaps Lyon’s species still persists, forgotten, in some garden or arboretum?
Since this shrub is only recently discovered, there remains the possibility of new populations being discovered. Steve reports that the shrubs are easiest to spot from a distance in October-November. The distinctive flowers open in late December to early February; hence the best time to look for big-leaf witch-hazel is during “hunting season.”