Standardized Common
Name: Black Haw
Other Common Names: American Sloe,
Nannyberry, Sweet Haw, Sweet Viburnum
Family: Caprifoliaceae or
Adoxaceae
Taxonomy: Viburnum
includes about 175 species that are mostly native to the Northern Hemisphere,
especially Asia, with a second center of diversity in Latin America. Viburnum
prunifolium belongs to Sect. Lentago, which comprises 5 species in
eastern North America and 1 species in Mexico.
Description: Large shrub or small
tree to 7(–10) m high; trunk to to 25 cm in diameter, frequently branching,
bearing short spur branches; bark gray, with interrupted ridges or separating
into irregular flakes 0.5–1.7 cm broad; young twigs slightly hexangular. Leaves
varying greatly in shape, often elliptical to ovate or obovate,
(2.5–)3.5–9.5(–18) cm long, thin to somewhat leathery; petiole slightly winged;
base rounded to cuneate, often oblique, tapering into petiole; apex variable;
margins serrate to serrulate; upper surface often bearing reddish stellate
hairs along midrib; venation pinnate. Inflorescences mostly terminal on short
spur branches, cymose, 3.5–12 cm broad, many-flowered, bracteate. Flowers
small; calyx 5-lobed; petals 5, white, basally fused, 2–3 mm long; stamens 5,
longer than corolla, filaments basally attached to petals; ovary inferior,
stigma 3-lobed. Fruit a berrylike drupe, persistent on the tree, sweet-fleshed,
black to blue-black, glaucous, ellipsoid to subglobose, 7–16 mm long, with
persistent calyx ring at apex, containing 1 large pyrene (“seed”); pyrene
laterally flattened, with a small tubercle at one end.
Parts
in Commerce:
Bark (root bark also used)
Identification:
- Slightly curved,
channeled or quilled pieces, to 15 cm long
- Thickness
variable, up to 6 mm
- Outer bark dull,
grayish, sometimes with raised lenticels; older bark often fissured or
scaly, sometimes irregularly coated with flat gray lichens
- Inner surface
yellowish to reddish-brown, usually longitudinally striated, sometimes
with cream to yellow wood fragments adhering
- Fracture short,
granular, uneven
- In transverse
section, has brown multilayered cork; narrow cortex, if not lost; pale or
reddish secondary phloem containing yellowish, irregularly shaped clusters
of stone cells (in older bark, extra layers of cork arise in cortex or
outer phloem, and outer layers peel off)
- Odor weak but
characteristic; when moistened, slightly resembles valerian
- Taste bitter and
astringent
Root
bark is 1–4 mm thick, and the fracture is more brittle than in stem bark. The
outer layer is dull brown or, if the cork has scaled off, reddish or yellowish
brown.
Viburnum
opulus
L. (Cramp Bark),
a European species, is used similarly and has similar appearance, taste, and
anatomy. The two can be distinguished only by using chemical methods such as
TLC. Other potentially substituted species of Viburnum have purplish
rather than grayish bark, or have large amounts of wood adhering to the inner
bark layer.
References:
British Herbal Medicine
Association. British Herbal Pharmacopoeia. BHMA; 1996:37–38.
Fernald ML. Gray’s Manual of Botany, 8th ed. New York: American Book
Company; 1950:1338–1342.
Jones TH. A Revision of the Genus Viburnum
Section Lentago (Caprifoliaceae). PhD. Dissertation, North Carolina
State University at Raleigh; 1983.
McAtee WL. 1956. A Review of the Nearctic
Viburnum. Chapel Hill, NC; 1956.
Wichtl M, ed. Herbal Drugs and Phytopharmaceuticals, 3rd English ed. Stuttgart:
medpharm Scientific Publishers and Boca Raton, FL: CRC Press; 2004:643–645.
Youngken HW. Text-Book of Pharmacognosy, 5th ed. Philadelphia, PA: The
Blakiston Company; 1943:836–844.