CANELO HILLS LADIES’ TRESSES } Spiranthes delitescens
DESCRIPTION: Canelo Hills ladies’ tresses are slender, erect terrestrial orchids that reach heights of about 20 inches when in flower. Five to 10 grass-like leaves grow basally on the stem, and the top of the flower stalk contains up to 40 small, white flowers arranged in a spiral.
HABITAT: The plant lives in marshy, mid-elevation cienegas surrounded by arid environments. It is supported by finely grained, highly organic, and perennially saturated soils, and is associated with perennial streams and stream headwaters.
RANGE: Canelo Hills ladies’ tresses have been found at five sites in the mountains of southeastern Arizona in the San Pedro River Watershed in Santa Cruz and Cochise counties.
LIFE CYCLE: Canelo Hills ladies’ tresses are presumed to be perennial, but mature plants rarely flower in consecutive years, and in some years have no visible above-ground structures. Plants may remain in a dormant, subterranean state or remain non-flowering for more than one consecutive year. The time needed for subterranean structures to produce growth is unknown.
THREATS: Canelo Hills ladies’ tresses are threatened by habitat loss and degradation caused by livestock grazing, groundwater pumping, and water diversion. The plants are also adversely affected by competition with nonnative species such as Johnsongrass and Bermuda grass, illegal collection, and possibly fire suppression.
POPULATION TREND: Five populations of Canelo Hills ladies’ tresses existed as of 2007. Estimating population size and stability is difficult because nonflowering plants are hard to find and dormant plants go uncounted.