Calopogon tuberosus (L.) BSP.


The genus is restricted to the United States. Five species can be found in the southeastern U.S., but only one is found north into Wisconsin. The genus Calopogon derives it name from the Greek terms kalos and pogon which mean, respectively, "beautiful beard" and apparently refer to the cluster of hairs that adorn the labellum. The specific epithet tuberosus is the Latin meaning "tuberous," in reference to the tuberous corm of this species.

DESCRIPTION: Plant arising from a small, oblong corm rather loosely attached to the substrate in which is growing (typically Sphagnum). One leaf, basal, grass-like, 10-30 cm long and 3-16 mm wide. Inflorescence a terminal raceme of 4-12 bright magenta to pink (rarely white) flowers. Inflorescence ranging from 10-40 cm high, each flower subtended by a lanceolate bract 4-8 mm long and about 2 mm wide; . Sepals ovate to obovate or elliptical, 1.5-2.5 cm long and 5-13 mm wide. Petals oblanceolate or elliptical, 1.5-2.5 cm long and 3-10 mm wide. Labellum uppermost (flower not resupinate) and appearing obovate, 1-2 cm long and 6-15 mm wide; center of the labellum bearing numerous yellow-tipped whitish hairs.

The plants are difficult to identify (or even locate) unless flowering, but then they can be confused with little else. Two slightly similar species that grow in similar habitat and flower at about the same time are Arethusa bulbosaand Pogonia ophioglossoides.

Calopogon can be found in two distinct habitat types in Wisconsin. The most common habitat is acid-soiled boggy areas, typically growing in Sphagnum. The other habitat is moist prairie. Calopogon is rarely found today in moist prairies, primarily as result of habitat loss.

June 20-August 10.

Thien & Marcks (1972) described the pollination of Calopogon tuberosus in some detail. The brush of hairs on the lip apparently serves as a "pseudopollen" lure, attracting naive, recently emerged bumblebees. The bees, expecting a reward of nectar and/or pollen, land on the hairs. At this point, the hinged labellum swings down under the weight of the bee and positions the bee on the column, where pollen can be placed on its back. If the bee already carries a load of pollen, it will contact the stigma and thus pollinate the plant.

DISCUSSION: Calopogon is one of the few native North American orchids that grows readily from seed under aseptic conditions (that is, non-symbiotic germination). Plants also grow rapidly to flowering size. Cyp Haven sells cultivated plants of Calopogon. As always, it is recommended that you buy cultivated plants from a reputable source, rather than remove them from the wild.

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