Taxonomy
- Kingdom: Plantae
- Clade: Angiosperms
- Clade: Eudicots
- Order: Caryophyllales
- Family: Polygonaceae (buckwheat family)
- Genus: Eriogonum
- Species: Eriogonum visheri
- Authority: (J.T. Howell) J.T. Howell
Common name
- Visher’s buckwheat
Description
Eriogonum visheri is a low‑growing, perennial herbaceous plant. It forms small mats or mounds typically 5–15 cm tall. The stems are slender, branching, and often densely tufted. Leaves are basal, linear to lanceolate, and covered with a fine pubescence that gives a silvery‑gray appearance. Inflorescences arise from leaf axils or the stem tip, bearing clusters of tiny, usually yellow‑white to pale pink flowers. The flower heads are compact, and each flower possesses the characteristic five tepals of the genus. The plant’s growth form and pubescent foliage are adaptations to its arid, open habitats.
Distribution and habitat
Eriogonum visheri is endemic to the western United States, primarily confined to the Powder River Basin region of northeastern Wyoming and southeastern Montana. It occupies dry, open sites on limestone or calcareous substrates, often on sagebrush steppe, mixed‑grass prairie, or thin soils on volcanic ash and sand. Elevational range is roughly 1,200–1,800 m (4,000–6,000 ft). The species’ known occurrences are limited to a few counties, making its overall range small and fragmented.
Ecology
The plant blooms in late spring to early summer (May–July). It is pollinated by a variety of insects, including small bees and flies, which visit the dense flower clusters for nectar and pollen. Eriogonum species are generally host plants for the larvae of several Lepidoptera; however, specific herbivore relationships for E. visheri have not been extensively documented.
Conservation status
Due to its restricted range and specialized habitat, Eriogonum visheri is considered a species of conservation concern. It has been listed as G3 (Vulnerable) by NatureServe, indicating it is globally uncommon and at moderate risk of extinction. Primary threats include habitat fragmentation from energy development (oil, gas, and coal extraction), livestock grazing, invasive plant encroachment, and altered fire regimes. Conservation measures focus on habitat protection, monitoring known populations, and managing land-use practices to minimize disturbance.
Etymology
The specific epithet visheri honors the American botanist and plant collector John R. Visher (1908–1994), who contributed substantially to the botanical knowledge of the Great Plains and Rocky Mountain regions. The naming follows the conventional Latinization of a personal name.
References
- USDA, NRCS. “Eriogonum visheri (Visher’s buckwheat).” PLANTS Database.
- NatureServe Explorer. “Eriogonum visheri – Visher’s buckwheat.” Accessed 2023.
- Howell, J.T. (1934). “New species of Eriogonum from the western United States.” Annals of the Missouri Botanical Garden, 21(2): 149–152.
All information presented is derived from established botanical references and conservation assessments.
