Subtribe Spiranthinae - The Pollination Biology of North American Orchids: North of Florida and Mexico - page 24

Fig. 2.3 Columns and pollinia. ( a )-( c ) Spiranthes ochroleuca ; ( d )-( f ) S. lucida. Columns viewed
from below ( left ); pollinia, ventral view ( center ), lateral view ( right ), scale bars = 1 mm. po pollinia,
ro rostellum, sg stigma, vs viscidium
Distribution and Habitat
S. cernua commonly forms colonies in usually acidic, sunny areas of marshes,
meadows, and woodland openings. It is found from Nova Scotia to Georgia and
west to southern Ontario, Minnesota, and Texas (Luer 1975 ; Catling 1980b ; Sheviak
and Brown 2002 ). S. ochroleuca prefers dryer and shadier sites than S. cernua and
occurs in developing woodland or meadows and barrens. It ranges from Nova Scotia
to Tennessee and South Carolina west to Michigan and Indiana (Sheviak and Brown
2002 ). S. magnicamporum may be present in wet prairies and fens but is frequently
found on dry, grassy uplands in calcareous soil, where it is largely isolated ecologi-
cally from S. cernua (Catling and Brown 1983 ; Catling 1990 ; Sheviak and Brown
2002 ). It ranges continuously from western Nebraska to Indiana, north to southern
Manitoba, and south to Texas, with scattered populations occurring east and west of
this region (Luer 1975 ; Sheviak and Brown 2002 ; Johnson 2006 ).