Facts About

Accepted Synonyms: none

Spiranthes casei, commonly called Case's Ladies' Tresses, has a limited distribution in northeastern Canada and the United States, from Wisconsin to Nova Scotia. It produces 2-5 basal and lower stem leaves, which wither at the time of flowering, and its upper stem and flowers are covered in thin hairs. It produces a spiraling inflorescence of up to 40 white or greenish cream-colored flowers, with a leafy green floral bract extending out from each flower. The labellum has two prominent calli. It can be found in mesic to dry meadows, open woodlands, and barrens and favors sandy, dry soils. It can be distinguished from S. magnicamporum by its scentless flowers and appressed, instead of spreading, sepals; it can be distinguished from S. cernua by its single, instead of multi-ranked, inflorescence and by its smaller flowers.

Spiranthes casei is apparently secure globally, although it is rare in the eastern part of its range.

Pollination

Bombus terricola and halictid bees such as Lasioglossum versans are documented pollinators for this orchid which may also be autogamous and capable of agamospermy.

Notes on Subspecies and Varieties

There are two varieties of Spiranthes casei:
Spiranthes casei var. casei has a slightly frilled labellum, is distributed across a wider range, and slightly larger flowers.
Spiranthes casei var. novaescotiae is found only in Nova Scotia, has slightly smaller flowers, and its labellum has an acute apex.

Ecosystem Type

Meadows, woodlands

Characteristics

Native to North America

Yes

North American Conservation Status & Distribution