Hamamelis virginiana L. Standardized Common
Name: Witch Hazel
Family: Hamamelidaceae
Taxonomy: Hamamelis
includes four species, of which two are native to North America. There are
several synonyms for H. virginiana, none commonly encountered in
literature. Hybridization with the other North American species, H. vernalis
Sargent (Ozark witch hazel), seems to be limited and does not blur species
boundaries.
Description: Shrub or small tree,
to 6(–10) m tall, often forming clumps, sometimes suckering; bark gray to
grayish brown, smooth to slightly rough. Leaves alternate, stipulate, broadly
elliptic to obovate or suborbicular, (3.5–)6–14(–16.5) cm long; base oblique,
cuneate to rounded; apex acute to acuminate or rounded; margins sinuate and
often ciliate; both surfaces pubescent with stellate and simple hairs, the
upper surface becoming nearly glabrous with age. Flowers borne in clusters of
3; calyx small, 4-lobed; petals yellow, strap-shaped, 10–20 mm long; stamens 4,
short; staminodes 4, producing nectar; ovary inferior, 2-styled. Fruit a woody
capsule, 10–16 mm long, explosively dehiscent, 2-seeded; seeds black, glossy,
5–9 mm long.
Parts
in Commerce:
Leaves or bark
Identification:
Leaves
- Petiole
6–15(–20) mm long
- Blade obovate to
rhomboid or broadly elliptic or suborbicular, (3.5–)6–14(–16.5) cm long
- Base oblique,
cuneate to rounded or barely cordate
- Apex acute to
acuminate or rounded
- Margin sinuate
to crenate or occasionally sinuate-dentate, often ciliate
- Venation
pinnate, with secondary veins conspicuous, straight, running to margins
(those to widest portion of leaf usually forking once); higher order
venation visible, netted
- Upper surface
dark to olive green, nearly glabrous at maturity
- Lower surface
pale green, shiny, bearing tufts of stellate hairs around veins; small
round protrusions sometimes visible on blade
- Texture slightly
leathery
- Taste
astringent, somewhat bitter
Bark
- Mostly in
channeled pieces <2.5 cm broad
- <1.5(–2) mm
thick
- Outer surface of
grayish cork with transverse lenticels, smooth or somewhat scaly, but not
glossy; sometimes cork is peeled off and outer surface is exposed cortex,
pale reddish brown, smooth or faintly longitudinally striated
- Inner surface
pale reddish pink to reddish or yellowish brown, faintly striated,
sometimes with attached fragments of whitish xylem
- In transverse
section, contains grayish cork (if not removed), at least 10 cells thick;
narrow brown cortex; pale band of fiber cells; reddish pink phloem
- Fracture short in
outer portion, fibrous in inner portion
- Taste
astringent, bitter
Adulterants: Substitution of Corylus
avellana L. (European Hazel, also known as European hazelnut or filbert)
has been reported but is unlikely to occur in normal commerce, because the two
genera are easily distinguished and C. avellana is seldom found outside
cultivation in North America. The leaves of C. avellana have nearly
symmetrical bases and biserrate, sharp-toothed margins. The petioles and veins
are pubescent with unbranched glandular hairs, but there are no stellate hairs.
The outer bark is smooth and coppery brown, sometimes peeling in thin strips,
with a thin cork.
References:
Greenish HG. Materia Medica. Jodhpur: Scientific Publishers (India); 1920
reprinted 1999:38–39 and 255–256.
Meyer FG. Hamamelidaceae. In: Flora of North America
Editorial Committee, eds. Flora of North America, vol. 3. New York, NY:
Oxford University Press; 1997:362–367.
Wichtl
M, ed. Herbal Drugs and Phytopharmaceuticals,
3rd English ed. Stuttgart: medpharm Scientific Publishers and Boca
Raton, FL: CRC Press; 2004:264–270.
Figure 31: a–b, Hamamelis virginiana leaf and close-up.
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