Witch-hazel

The witch-hazels are deciduous shrubs or (rarely) small trees growing to 3 to 7.5 m tall, even more rarely to 12 m tall. The leaves are alternately arranged, oval, 5 to 15 cm long, and 2.5 to 10 cm wide, with a smooth or wavy margin. The genus name, Hamamelis, means "together with fruit", referring to the simultaneous occurrence of flowers with the maturing fruit from the previous year.[4] H. virginiana blooms in September–November while the other species bloom from January–March. Each flower has four slender strap-shaped petals 1 to 2 cm long, pale to dark yellow, orange, or red. The fruit is a two-part capsule 1 cm long, containing a single 0.6 cm glossy black seed in each of the two parts; the capsule splits explosively at maturity in the autumn about eight months after flowering, ejecting the seeds with sufficient force to fly for distances of up to 9 m, thus another alternative name "snapping hazel".

The name witch in witch-hazel has its origins in Middle English wiche, from the Old English wice, meaning "pliant" or "bendable", and is not related to the word witch meaning a practitioner of magic.[5] Jacob George Strutt's 1822 book, Sylva Britannica attests that "Wych Hazel" was used in England as a synonym for wych elm, Ulmus glabra;[6] The use of the twigs as divining rods, just as hazel twigs were used in England, may also have, by folk etymology, influenced the "witch" part of the name.[3]

Five species are recognized:[7]

• Hamamelis japonica Siebold & Zucc. – Japanese witch-hazel
• Hamamelis mollis Oliv. – Chinese witch hazel
• Hamamelis ovalis S.W.Leonard – big-leaf witch-hazel
• Hamamelis vernalis Sarg. – Ozark witchhazel
• Hamamelis virginiana L. – common witch-hazel or American witch-hazel

Hamamelis mexicana is sometimes considered a species,[8] though as of 2020 Kew's Plants of the World Online considers it a variety of H. virginiana.[7]

The Persian ironwood, a closely related tree formerly treated as Hamamelis persica, is now given a genus of its own, as Parrotia persica, as it differs in the flowers having just sepals and no petals. Other closely allied genera are Parrotiopsis, Fothergilla, and Sycopsis (see under Hamamelidaceae). Witch-hazels are not closely related to the true Corylus hazels, though they have a few superficially similar characteristics which may cause one to believe that they are.

They are popular ornamental plants, grown for their clusters of rich yellow to orange-red flowers, which begin to expand in the autumn as or slightly before the leaves fall and continue throughout the winter.

The main phytochemicals in witch-hazel leaves are polyphenols, including 3–10% tannins, flavonoids, and up to 0.5% essential oil, while the bark has a higher tannin content.[10][11] Hamamelis water, also called white hazel or witch hazel water prepared from a steam-distillation process using leaves, bark or twigs, is a clear, colorless liquid containing 13–15% ethanol having the odor of the essential oil, but with no tannins present.[10][11] Essential oil components, such as carvacrol and eugenol, may be present.[12]

As an ingredient and topical agent, witch-hazel water is regulated in the United States as an over-the-counter drug for external use only to soothe minor skin irritations.[13] Hamamelis (witch-hazel) water is diluted using water in a 1:3 preparation, and is not intended for oral use which may cause nausea, vomiting, or constipation.[11]

The leaves and bark of the North American witch-hazel, Hamamelis virginiana, were used in folk medicine, herbalism, and skincare decoctions by Native Americans.[10][11][3] Extracts of witch-hazel have been claimed to be effective for psoriasis and eczema, to prevent dehydration of skin, and for insect bites, poison ivy,[19] and razor burn.[20][21][22] There is limited clinical evidence to support witch-hazel as an effective treatment for any of these conditions.[11] Prepared by distillation, the essential oil of witch-hazel has such a small proportion of tannins or other polyphenols that it is unlikely to have any therapeutic effect, and may cause contact dermatitis when used topically.[10][11]

In 2017, one manufacturer of skin care products containing witch-hazel was warned by the Food and Drug Administration for making unsubstantiated health claims and for not providing evidence the products were safe.[23]

Early Puritan settlers in New England adopted witch-hazel as a supposed remedy from the natives, and its use became widely established in the United States during the 19th century.[19] A missionary, Dr. Charles Hawes, adopted the process of steam distillation of witch-hazel twigs,[19] creating a "Hawes Extract" product sold in Essex, Connecticut, in 1846, by druggist and chemist, Alvan Whittemore.[24] Hawes' process was further refined by Thomas Newton Dickinson, Sr., who is credited with starting the commercial production of witch-hazel extract, also in Essex, Connecticut, in 1866, and eventually establishing nine production sites in eastern Connecticut during the 20th century.[19][25] Following his death, his two sons, Thomas N. Dickinson, Jr., of Mystic, Connecticut, and Everett E. Dickinson of Essex, each inherited parts of the family business and continued the manufacture of witch-hazel extract, operating competing "Dickinson's" businesses that their descendants continued until 1997 when the manufacturing operations from both companies were consolidated at the American Distilling plant in East Hampton, CT.[19]

• 
  Hamamelis flowers, Menai Bridge, Wales
• 
  Hamamelis, Fürth City Park, Germany
• 
  Hamamelis, Colonial Park Arboretum and Gardens
• 
  H. × intermedia
• 
  Hamamelis japonica close-up flowers
• 
  H. × intermedia 'Jelena'
• 
  H. × intermedia 'Diane'
• 
  Hamamelis mollis tree in autumn
• 
  Hamamelis mollis in autumn
• 
  Hamamelis mollis leaves in autumn
• 
  Winter-flowering, Vogelsberg Mountains
• 
  Flourishing in winter

• Fergus, Charles (2002). Trees of Pennsylvania and the Northeast. Stackpole Books. pp. 156–9. ISBN 978-0-8117-2092-2.
• Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Macmillan.