Spiranthes incurva

Spiranthes incurva sphinx ladies’-tresses

Plant grows in the wild/spontaneouslyPlant is native to PA

Spiranthes incurva was first described by Matthew Pace and Kenneth Cameron in 2017 as an ancient hybrid of S. cernua and S. magnicamporum that has emerged as a self-sustaining species.  Its flowers are ivory to white, often parallel to the ground or rising as opposed to nodding, with a long, pointed labellum and rising lateral sepals which at first glance look attached to the upper petal.  Flowering time is earlier than most members of the S. cernua complex – it can often be found at peak bloom in our area by the third or fourth week of August, although some plants may still be found in flower as late as mid-September.  

S. incurva can grow up to 20 inches tall and has 1 to 5 long, narrow leaves that usually wither by the time it blooms. It is found in wet areas from fens to roadside ditches but is also found in dryer sand dunes along the Great Lakes.

This species dominates the northern limit of the S. cernua complex – its range stretches from the Great Lakes across to Maine and Southern New Brunswick before giving way to S. cernua s.s. near to the Atlantic coast.  It appears to be limited to the northern third of Pennsylvania but may grow in areas further south as well.  Plants collected by Otto Jennings on Presque Isle in Erie County near the start of the 20th Century serve as the type specimens. 


Pace, M.C. and K.M. Cameron. 2017. The systematics of the Spiranthes cernua species complex (Orchidaceae): Untangling the Gordian Knot. Systematic Botany, 42(4):1–30.

Hough, Michael and Matthew Young. 2021.  A Systematic Survey of the Spiranthes cernua Species Complex (Orchidaceae) in New York.  The Native Orchid Conference Journal, 18.3: 22-56.

Contributed by: Greg Funka

Grows in various wet areas.

Mostly found in northern part of the state.

Wetland code: Not classified

Flowers mid-August to mid-September.

S-rank:  No rank
G-rank:  No rank