2. Calopogon R. Br. (grass pink)
with tuberlike corms. Flowering stems erect, with 2–10 nonresupinate flowers in
a raceme at the tip. Leaf 1(–2), basal, 5–35 cm long, green, herbaceous,
glabrous, linear‑lanceolate. Sepals 14–25 mm long, the lateral sepals
ovate with oblique tips, the upper sepal narrowly elliptic. Lateral petals
14–22 mm long, oblong‑elliptic. Lip 11–17 mm long, linear, and broadened
at the tip into 2 or 3 circular to triangular lobes, bearded with dense, club‑shaped
hairs below the lobes. Column 9–18 mm long, pink, 2‑winged near the tip.
Stamen 1, staminodes lacking. Capsules erect, 18–21 mm long, elliptic in
outline, strongly ribbed. Five species, eastern North America.
recently, grass pinks in the state were treated as a single species by most
authors. Summers (1981) first discussed the fact that in Missouri these orchids
exhibit two morphological phases that coincide with dissimilar habitats.
Subsequently, Magrath and Nelson (1989) examined similar variation in Oklahoma plants and treated them as C. tuberosus var. tuberosus and var. simpsonii
(Chapman) L. Magrath. Goldman (1995) concluded that these phases represent
distinct species, and his classification is followed below.
flowers of Calopogon are pollinated by bees, which are apparently
deceived by the beard of hairs on the column that resembles anthers. The hinged
lip, which is at the top of the flower, flexes downward when a bee lands on it,
forcing the insect to pollinate the flower during its escape.