Boschniakia is a small genus of holoparasitic flowering plants in the family Orobanchaceae (broomrape family), order Lamiales. Commonly known as groundcones, these plants are native to western North America and extreme northeastern Asia. They contain little or no chlorophyll and depend entirely on host plants for water and nutrients, which they obtain through specialized structures called haustoria that penetrate the roots of their hosts. Alders (Alnus spp.) are frequently parasitized, though groundcones are found on a variety of woody plants.
The name "groundcone" reflects the plant's striking appearance: the above-ground portion consists almost entirely of a dense, upright inflorescence packed with thick, cup-shaped flowers, giving the plant a pine-cone-like shape when it emerges from the soil. Plants are typically a few inches tall and may be brown, yellow, red, or purple in color.
The circumscription of Boschniakia is disputed. Some taxonomists treat it broadly to include species sometimes placed in the segregate genera Kopsiopsis and Xylanche. In the narrow treatment, only a single species remains: Boschniakia rossica (the northern groundcone). The original type species, Boschniakia glabra, is no longer considered a valid name and is subsumed within Boschniakia rossica.
Distribution
Boschniakia is native to western North America and extreme northeastern Asia. The plants grow in association with their host plants — most often alders — across boreal, subarctic, and montane habitats within this range.
Ecology
Groundcones are holoparasites: they produce no chlorophyll and rely entirely on host plants for nutrition. They attach to host roots via haustoria. Alders (Alnus spp.) are a frequent host, though the plants occur on a range of other woody species. Above ground the plant is almost entirely its inflorescence, remaining inconspicuous until it emerges to flower and fruit.
Taxonomy Notes
The genus boundaries of Boschniakia are contested. Some taxonomists recognize only Boschniakia in a broad sense, encompassing species placed by others in Kopsiopsis and Xylanche. In the narrow circumscription, the genus contains a single species, Boschniakia rossica. The original type species, Boschniakia glabra, is treated as a synonym of Boschniakia rossica.
