Western blackhaw (Viburnum ellipticum) is a shrub that is native to the western United States. This species is a host to the holly blue (Celastrina argiolus), Spring Azure (Celastrina ladon), Henry’s elfin (Incisalia henrici) and the baltimore checkerspot (Euphydryas phaeton). Growing from 4 feet to 12 feet tall, this species grows generally in wet areas such as rocky slopes, open woods, and forests. The white flowers bloom from March to June and the plant is hardy in zone 6.
Taxonomy and Naming of Western Blackhaw (Viburnum ellipticum)
Taxonomy
Western Blackhaw (Viburnum ellipticum) was originally named and described by William Jackson Hooker, an English botanist, in 1832. It has kept this same name since and is a member of the Muskroot Family (Adoxaceae).
Meaning of the Scientific and Common Names
Scientific Name
The genus name, Viburnum, derives from the Latin word for obscure or wayfaringtree. The species name, ellipticum, is Latin for “elliptical”, presumably for the shape of the leaves.
Common Name and Alternative Names
The common name comes from the native location of the species on the west coast of the United States. Another common name is Oregon viburnum (Olmstead 1923) and western viburnum.
Physical Description
- Plant Type: This plant is a shrub.
- Height: 4 ft (1.2 m) to 12 ft (3.4 m)
- Stem: There are multiple stems with light brown to gray bark that is hairless.
- Leaves: The leaves are simple, opposite, orbicular, ovate to elliptical and have dentate, serrate, or crenate margins. They are 1.2 in (3.0 cm) to 4 in (10.2 cm) long and 0.8 in (2.0 cm) to 3 in (7.6 cm) wide. The leaves are three to five nerved from the petiole (Abrams and Ferris 1960) and rounded at both ends (Howell 1903).
- Flower color: white
- Blooming period: This plant blooms from March to June.
- Fruiting type and period: This plant has reddish-brown to black drupes that mature in the late summer to fall.
Range of Western Blackhaw in the United States and Canada
This Viburnum is native to the western United States. It is considered to rare in the state of California.
Habitat
This species grows on rocky slopes and open woods (Muenscher 1951), oak-woodland and cottonwood forest (Christy, et al 2009), cedar-hemlock forests (Clements 1920), and rocky ridges (Howell 1903).
Hosted Insects
This viburnum is a host to the holly blue (Celastrina argiolus), spring azure (Celastrina ladon), Henry’s elfin (Incisalia henrici), the Baltimore checkerspot (Euphydryas phaeton), and the scarce fritillary (Euphydryas maturna).
Other Supported Wildlife
This species is a nectar source to other butterflies, skippers, bees, and wasps during the growing season. Birds enjoy the fruits in the fall.
Frequently Asked Questions
Does this plant have any ethnobotanical uses?
The Native American Ethnobotany Database notes that this species has been used as a contraceptive and an orthopedic aid.
How is this plant distinguished from other Viburnums?
This species is very similar to the southern arrow-wood (Viburnum dentatum), however, while the southern arrow-wood has pubescent petioles, this species does not (Weakley 2022). The peduncles are also glabrous for this species (Dobbs 1952). It is also close to squashberry (Viburnum edule), but its leaves are rounded and generally three lobed (Piper and Beattie 1915).
Is this plant invasive?
This species has not been noted as being weedy.
Gardening with Western Blackhaw
Hardiness
This species is hardy in zone 6. If your garden is within these zones and you have the right growing conditions (soil, moisture and exposure), you may well be able to grow this plant. However, if planted outside of its range, the hosted species may not recognize the plant or be harmed by ingesting a different species with an unfamiliar chemical composition.
Optimal Conditions
This species requires full sun and dry to medium well-drained soils.
References
- Abrams, Le Roy and Roxanna S. Ferris. 1960. An illustrated flora of the Pacific States: Washington, Oregon, and California. (Stanford University: Stanford University Press).
- Christy, J.A., A. Kimpo, V. Marttala, P.K. Gaddis, and N.L. Christy. 2009. Urbanizing flora of Portland, Oregon, 1806-2008. Native Plant Society of Oregon Occasional Paper 3: 1-319.
- Clements, Frederic E. 1920. Plant Indicators: The Relation of Plant Communities to Process and Practice. Carnegie Institution of Washington 290.
- Howell, Thomas. 1903. A flora of northwest America: containing brief descriptions of all the known indigenous and naturalized plants growing without cultivation north of California, west of Utah, and south of British Columbia. Vol. 1.
- Muenscher, W.C. 1951. Native Viburnums of North America. The Arboretum Bulletin 14 (3): 15-16 and 25.
- Olmstead, Frederick Law. 1923. Standardized plant names; a catalogue of approved scientific and common names of plants in American commerce. (Salem, MA: American Joint Committee on Horticultural Nomenclature.
- Piper, Charles V. and R. Kent Beattie. 1915. Flora of the northwest coast, including the area west of the summit of the Cascade Mountains, from the forty-ninth parallel south to the Calapooia Mountains on the south border of Lane County, Oregon. (Lancaster, Pa: Press of the New Era Printing Company).
