Spiranthes romanzoffiana

Spiranthes romanzoffiana hooded ladies’-tresses

Plant grows in the wild/spontaneouslyPlant is native to PA

The stems of all of the species in this genus tend to spiral. This one, like the nodding ladies’ tresses (S. cernua) usually have a double spiral and somewhat resembles braided hair. The cream white flowers, however, are more densely packed on the spike than on the nodding ladies tresses. The flowers of the hooded ladies tresses’ also do not nod downwards. The lower lip of the flower is constricted near the middle somewhat like a violin. The lateral petals and combine with the upper sepal to form a hood. Each flower is about ½ inch long and the flower spike may contain up to 40 individual blooms. The inflorescence may be covered with fine hairs. In spite of the abundance of flowers this species does not often seem to produce seeds.

All known reproduction in North America seems to be vegetative, but the method by which this might occur is not known. Genetic studies have shown considerable variation in the chromosome number of plants in various locations. The 2-5 basal leaves are grass-like in appearance. This species grows in wet meadows, fens, bogs and a variety of moist environments in Canada, Alaska and the northern United States. It is also found in Ireland and the British Isles. In Pennsylvania it is historically documented only in Erie and Lawrence Counties. It is considered Endangered in the state. The blooming season is late summer and early autumn. It is also called the Irish lady’s tresses.

Contributed by: Mark Welchley

Very rare in bogs or rich, open woods.

Found in the northwest of the state.

Wetland codes
EMP: OBL
NCNE: OBL



Flowers July to August.

PA status: PE (Enangered)
S-rank:      S1 (Critically imperiled)
G-rank:      G5 (Secure)