Montana Field Guide

PLANTS: A long-lived perennial plant, usually with a single stem, 3-20(-40) cm tall, that grows from a thickened, tuberous root. Source: Lesica et al. 2012.

LEAVES: Narrow, linear leaves about 1 cm wide and up to 20 cm long. Leaves are longest at their base, becoming shorter towards the inflorescence, and persist during flowering. Source: Lesica et al. 2012.

INFLORESCENCE: A terminal bracteate spike that is glandular-puberulent, 2-8 cm long. Few to many, white or ivory flowers spiral around the upper stem, in a 3-rank pattern. Bracts are 6-12 cm long. Flowers are perpendicular to the stem, 6-merous, but there is merger in each of the uppermost petals or sepals and lowermost petals or sepals. Upper, lower, and lateral sepals are greenish. Upper sepals and upper petals are crowded together, united below, and form a forward-pointing hood. Lateral sepals are separate or may be slightly connate at their base and often spread abruptly apart. Lip petal is 6-9 mm long, tongue-shaped yet narrowed at the middle, points downward, is wavy-margined, and is blunt at the tip. Hood formed by petals and sepals is 7-12 mm long. Source: Lesica et al. 2012.

The genus Spiranthes comes from the Greek words of "speira" which means coiled and "anthos" which means flower. They refer to the spirally arranged inflorescence. Charles Sheviak described the species and chose the specific epithet of "diluvialis", which comes from the word "diluvium" meaning "flood"; it refers to the species' moist habitat that temporarily floods in what is otherwise an arid environment (Sheviak 1984).

The common name of "Ladies'-tresses" refers to the inflorescence which resembles the braided locks of hair worn by women (USFWS 1990). The common name of "Ute" was given by the USFWS to recognize that the plant's historic range was largely used by the Ute Indian Tribe (USFWS 1990).

NATIONAL LINK - IDENTIFICATION
Go Orchids-North American Orchid Conservation Center

Ute Ladies'-tresses flowers from July to early September across its range (Sheviak and Brown in Flora of North America (FNA)). In Montana flowering typically occurs in August to early September, but often is not in full flower until mid-August.

Ute Ladies'-tresses was first collected in Colorado in 1856 and in Utah in 1880. However, it was not recognized as a unique species until 1984 when Charles Sheviak realized it represented a suite of different morphological characteristics (Sheviak 1984).

Ute Ladies'-tresses - Spiranthes diluvialis, Federally Threatened, SOC
*Inflorescence: Flowers in the spike are spaced further apart, less dense. Flowers spiral on the spike creating 3-ranks or columns.
*Upper Sepals/Petals: Form a less distinct hood and are more long and slender. Both are separated for most of their length, connecting only at their base. Hood is 7-12 mm long.
*Lip Petal: Clearly visible when viewed from the side. Petal is not constricted in the middle and has a blunt tip. Spur is absent.
*Habitat: Wet, calcareous, riparian meadows in valleys.

Hooded Ladies'-tresses - Spiranthes romanzoffiana
*Flowers: Flowers in spike are densely crowded. Flowers spiral on the spike creating 3- or 4- ranks or columns. Flowers grow more upright.
*Upper Sepals/Petals: Sepals are partially fused and united with the petals, forming a true hood over the stamens and pistil. Hood is shorter, 5-10 mm long.
*Lip Petal: Partially hidden by the hood, making it difficult to see when viewed from the side. Petal is constricted in the middle, like a violin, and has an acute tip. Spur is absent.
*Habitat: Wet meadows, fens, and occasionally in grasslands, from valleys to subalpine.

Bog Orchids - Platanthera species
*Flowers: Arranged in a spike-like raceme, but do not spiral around the stalk.
*Lip petal: Forms a downward pointing spur.
*Leaves: Either basal or leafy along entire stem. Those on the stem are sheathing, alternately-arranged, and whither during flowering.

Rein Orchids - Piperia species
*Flowers: Arranged in a spike-like raceme, but do not spiral around the stalk.
*Lip petal: Forms a downward pointing spur.
*Leaves: Basal and on the lower third of the stem. Those on the stem are sheathing and may be arranged opposite or alternate.

In Montana plants grow in calcareous wetlands, swales, and old meander channels that are outside of the active stream channel (Heidel 2001; Lesica et al. 2012). Within these habitats plants often grow at the wetland edges or in areas that dry by mid-summer. Plants can occupy small, fragmented parcels of habitat.

Populations are maintained by conditions that maintain an early-seral habitat stage. These conditions could include alkaline or calcareous soils, seasonal flooding, and grazing.

In sites with an open canopy plants flower earlier while in well-shaded sites plants flower later (Jennings 1989).

POLLINATION [Adapted from Fertig et al. 2005]
Flowers of Ute Ladies-tresses are primarily pollinated by solitary bees (Anthophora spp.) and bumble bees (Bombus spp.), and sometimes by non-native honey bees (Apis mellifera). Bombus fervidus has been reported as a pollinator where its geographical distribution overlaps with Spiranthes (Colla and Dumesh 2010). Several studies in Utah concluded that orchids pollinated by Anthophora terminalis produce three times as many fruits as plants pollinated by Bombus species. Many long-term studies of pollinators have found that the abundance and composition of the bee fauna vary in any given year. Syrphid flies, skippers, and other hymenopteran insects have been observed on flowers of Ute Ladies'-tresses, but are thought to be either too small or improperly shaped to function as effective pollinators.

Within the inflorescence, the lower-most flowers open and mature before those that are higher up on the stalk. Each flower contains 1-2 stamens (male) and 1 pistil (female). The pollen-bearing anthers of the stamens mature before the stigma of the pistil is receptive. Thus, when a bee visits, the flowers are essentially unisexual, passing through a staminate stage before becoming pistillate. As flowers mature along the inflorescence those higher up on the stalk are staminate while those below are pistillate. Lured by a visual cue, bees visit the lowermost flowers first before proceeding up the stalk. Since the upper flowers are not receptive to the pollen (i.e., stigma is not yet sticky to catch pollen), pollen remains on the bee's back until if flies to a different inflorescence where it pollinates a receptive stigma on the pistil, and continues its foraging strategy.

The asynchronous maturation of flowers within an inflorescence promotes cross-pollination (outcrossing) between individual plants. However, staminate and pistillate stages may overlap in the same inflorescence, resulting in pollen from one flower fertilizing eggs in the pistil of another flower on the same plant. It is hypothesized that Ute Ladies'-tresses may be capable of agamospermy, which is a form of asexual reproduction in which seeds are produced without fertilization.

Plants are long-lived herbaceous, perennials that likely reproduce only by seed (Fertig et al. 2005). Occasionally plants are found to grow in clusters, but these are thought to result from either asexual reproduction from a single or broken root mass or germination from an entire capsule where multiple seeds germinated (Fertig et al. 2005).

FLOWERS
Stamens: 1 or 2, fertile, and unite with the style of the pistil to form a column (Lesica et al. 2012). Pistil: 1 style and a 3-celled, inferior ovary.

Flowers have a vanilla-like scent (Fertig et al. 2005). Within the spike, the lower-most flowers bloom first.

FRUITS
An ovoid capsule, 10-15 mm long that opens longitudinally to expose many seeds (Lesica et al. 2012; Fertig et al. 2005).

LIFE CYCLE [Adapted from Fertig et al. 2005]
Over a lifetime, individual Ute Ladies'-tresses exhibit four main stages which occur in no particular order or for any particular length of time: seedling, dormant, vegetative, and reproductive. The life cycle is charted in Fertig et al. (2005). In most years, a portion of a population will exhibit dormancy, while others will flower, and the remainder will be in a vegetative stage. The relative proportion of plants in each life stage will vary by year and between populations. Life stages may be triggered or suppressed in response to grazing, pollinator success, climate, habitat disturbance, and management practices. Refer to the MANAGEMENT section.

Fruiting and Seed Development
Across its range, fruits (capsules) are produced from late August to September and seeds are shed shortly after. Orchids are known to have microscopic, dust-like seeds that easily disperse by wind or water, and the seeds of Ute Ladies'-tresses are no exception. Capsules may contain from several hundred to several thousand seeds, and a single plant could produce 100,000 seeds in a year. Their tiny size indicates that seeds contain very little stored food which is required to sustain the embryo; therefore, seeds are likely very short-lived once they contact the soil. At the Cincinnati Zoo and Botanical Garden in Ohio, seeds of Ute Ladies'-tresses were cultured in the lab but took 1.5 years for germination to occur. In the natural world, it is hypothesized that germinated seedlings must quickly establish a symbiotic relationship with soil-dwelling mycorrhizal fungi in order to survive. The absence or presence of appropriate mycorrhizal fungi in the soil may limit population sizes. Seedlings may persist for up to 8 years as subterranean saprophytes dependent on mycorrhizal fungi (Heidel 1998). Other Spiranthes species have shown they can remain dormant for 8 to 11 years (Wells 1981).

Subterranean Dormant Stage
It is unknown at what age germinated plants must be in order to develop above-ground leafy shoots. At some age, possibly 8 to 11 years, plants emerge above the ground. Long-term demographic monitoring of Ute Ladies'-tresses demonstrated that vegetative or reproductive individuals can re-vert to a below ground dormant stage for 1 to 4 years, or longer, before re-emerging above ground. Although plants are considered to be dormant, subterranean plants remain metabolically active and derive nourishment from their mycorrhizal partners or food stores laid down when photosynthetic shoots were present.

Vegetative Stage
Vegetative shoots develop in October and persist through winter as small rosettes. In the spring growth resumes, developing into short-stemmed, leafy, photosynthetic plants. They remain vegetative or they may develop an inflorescence, depending upon the site's productivity and conditions. Come winter the vegetative shoot dies back to subterranean roots and leaves persist as a winter rosette. Demographic monitoring demonstrates that vegetative plants can remain in this stage for 2 or more years or can transform to a dormant subterranean stage or can become reproductive in subsequent years.

Reproductive Stage
Across its range Ute Ladies'-tresses blooms from early July to late October. Life expectancy is estimated at more than 50 years based on a related Spiranthes species (Heidel 1998).
Refer to the ECOLOGY / POLLINATION section.

SPECIES ORIGINATION
It is hypothesized that during the Pleistocene epoch Spiranthes diluvialis arose as a hybrid between Spiranthes romanzoffiana and Spiranthes magnicarporum (Sheviak 1984); Spiranthes magnicarporum is not known from Montana. Spiranthes diluvialis is intermediate in its morphology between these putative progenitors. Hybridization resulted in an allopolyploid species (Spiranthes diluvialis). Allopolyploid species have a complete diploid set of chromosomes from each genetically distinct parent. It is the doubling of chromosomes in the hybrid that allows it to be fertile, but no longer cross-compatible with its parent species. As the climate during the Pleistocene became drier, these three plants responded by occupying different habitats:

*Spiranthes romanzoffiana retreated to higher, cooler, and wetter sites; today it is globally widespread, with a tendency to be found at northern latitudes or at higher elevations.

*Spiranthes magnicarporum retreated to warm, mesic sites; today it is a plains plant found in moist areas of the Midwest and east.

*Spiranthes diluvialis persisted in warm, wet sites. As the climate became more arid, Spiranthes diluvialis' habitat became more limited.

ENDANGERED SPECIES ACT
Recognizing that America's rich natural heritage is of esthetic, ecological, educational, recreational, and scientific values to our Nation and its people, the Endangered Species Act (ESA) was created to recover and protect imperiled species. The ESA of 1973 as amended by Congress provides for the conservation of endangered and threatened species of fish, wildlife, and plants, and for other purposes. The ESA mostly requires the U.S. Fish and Wildlife Service (USFWS) to: a) list, classify, protect, and recover species [Sections 4, 9, and 12], b) review and evaluate federal actions for potential affects to listed species [Section 7], c) oversee recovery activities [Sections 4, 5, and 6]; d) work cooperatively with the States [Section 6] and internationally [Section 8]; and e) provide exemptions (permits) for scientific efforts and conservation activities [Section 10]. The USFWS uses five main factors to determine if a proposed species warrants listing under the ESA: 1) present or threatened habitat/range loss, 2) overutilization, 3) disease/predation, 4) inadequacy of protections, and 5) other threats. The de-listing of a species is assessed using three criteria: 1) recovery, 2) extinction, or 3) erroneous information at the time of listing. The USFWS uses a Species Status Assessment to evaluate the resiliency, redundancy, and representation to understand the current and potential future viability of a species to inform listing, consultation, and recovery decisions (USFWS 2016; USFWS Species Status Assessment).

Ute Ladies'-tresses under the ESA
Ute Ladies'-tresses was listed as Threatened under the ESA on January 17, 1992 (USFWS 1992). Designated by the USFWS, Threatened Species are "any species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.

Ute Ladies'-tresses was listed as threatened because of habitat loss and modification, and the understanding that its small populations and low reproductive rates make it vulnerable to other threats (USFWS 1992). Specifically, habitat loss and modification were reported based on loss of riparian habitat, urban residential development, stream channelization, and construction projects (USFWS 1992). In addition, there were concerns that this plant could be over-collected by orchid enthusiasts and gardeners (USFWS 1992). At the time of listing, it was known only from north-central Colorado, south-central Utah, and southeastern Nevada. Since its listing surveys have found it in 9 states (Fertig et al. 2005); refer to the RANGE COMMENTS section. In 1994 Montana's first population was discovered; refer to the RANGE COMMENTS section. Surveys have resulted in finding new populations across a larger range where it is usually sparse and highly restricted on the landscape.

In 1995 a draft recovery plan was prepared by the Ute Ladies'-tresses recovery team (USFWS 1995). In 1996 the Central Utah Water Conservancy District petitioned the USFWS to delist Ute Ladies'-tresses on the grounds that it was sufficiently widespread and secure enough that it no longer warranted protection under the ESA. In 2004 The USFWS published a 90-day Finding that determined the petition had sufficient information that a Status Review should be initiated to determine if de-listing would be warranted (USFWS 2004). In 2005 the Range-wide Status Review of Ute Ladies’-Tresses was prepared for the USFWS and Central Utah Water Conservancy District by Fertig, Black, and Wolken (2005). Since 2005 direction on its status has been quiet until 2017. In 2017 the USFWS - Utah Field Office has begun the process to evaluate the status of Ute Ladies'-tresses. Funding from the USFWS and the State of Wyoming allowed the Wyoming Natural Diversity Database to develop a Predictive Distribution Model based on range-wide occurrence data.

Montana abides by federal Endangered Species regulations for listed plants as there is no state endangered law that specifically applies to vascular plants. Section 9 of the ESA regulates prohibitions. For threatened plants the following federal prohibitions apply:
* It is illegal to import or export (into, out of, or through the US) threatened plants.
* It is illegal to engage in interstate or foreign commerce with threatened plants.
* It is illegal to remove and reduce to possession threatened plants from Federal property (cultivated seeds excepted).

Other Designations
The Convention of the International Trade in Endangered Species (CITES) protects species from international trade and export. Ute Ladies'-tresses is listed in Appendix II of the CITES act.

LAND MANAGEMENT [Adapted from Fertig et al. 2005]
The effects of haying, mowing, and grazing come directly or indirectly from various studies and surveys conducted in Colorado, Nebraska, and/or Utah: Allison 2001, Arft 1995, Fertig 2000, Hazlett 1996 and 1997, Riedel 2002, and others. They have been nicely summarized by Fertig et al. (2005).

In Montana the management of haying, mowing, and livestock grazing has not been studied. A demographic monitoring study conducted in Jefferson County by a former MTNHP Botanist provided insights into population structure, population trend, dormancy rates, and some life history information (Heidel 2001). Management recommendations were to avoid direct negative impacts to flowering plants, reduce competing vegetation on an annual or periodic schedule, and conduct consecutive, multi-year monitoring to evaluate the effects of management on plant populations (Heidel 2001).

Haying/Mowing
Haying and mowing has been shown to be beneficial to populations if timed correctly. Mowing, especially in conjunction with winter grazing, can reduce competing vegetative cover and protective cover for voles which can have positive effects on Ute Ladies'-tresses (Fertig et al. 2005). Irrigating hay meadows could increase the amount of habitat that would otherwise not be available to Ute Ladies'-tresses (Fertig et al. 2005). Haying and Mowing needs to be done before the appearance of inflorescences, by mid-July or earlier, in order to not damage flower and fruit production.

Livestock Grazing
Grazing management practices can be beneficial to populations if timed correctly. Plants are edible to livestock. Summer grazing can trample plants and remove their inflorescence, which reduces fruit production, depending upon grazing intensity and site conditions. Winter grazing has been shown to be beneficial in Colorado because it reduces competing vegetation and escape cover for voles (Fertig et al. 2005). Ute Ladies'-tresses that grow in meadows that lack strong seasonal flooding may be dependent on a mix of winter grazing and mowing to maintain habitat conditions and their persistence (Fertig et al. 2005).

Survey and Monitoring Studies
Surveying, counting, and monitoring Ute Ladies'-tresses is a challenge because populations are small and plants can be cryptic. In any given year a portion of a population is absent due to dormancy and portions are present in vegetative and flowering stages. Dormant plants won't be observed. Vegetative plants are difficult to find because they are either short rosettes or leafy stems that visually blend in with adjacent vegetation. It is the flowering plants that will catch your eye because they are taller and terminate in a cluster of white flowers.

When flowering, plants are easy to locate. Presence/absence surveys must be done during the flowering stage, and preferably for 2-3 consecutive years. However, flowering plants are not a good indicator for mapping the boundaries of a site, counting the population size, or determining a population's trend. Demographic monitoring at the Piedmont site found flowering plants accounted from 5% to 46% of the entire population, depending upon the year (Heidel 2001). Demographic monitoring that maps individuals and identifies their vegetative, seedling, and reproductive stages over many consecutive years is necessary to accurately estimate population size, map distributions, and determine population trends of increasing, decreasing, or stable.

USEFUL LINKS
North American Orchid Conservation Center website

Across the range, current and potential long-term threats to Ute Ladies'-tresses includes habitat loss and modification (through urbanization, water development, and conversion of wetlands to agriculture), over-collection of plants, competition from exotic weeds, and herbicides (Fertig et al. 2005). In addition, plants are more susceptible to threats because their populations are usually small and their habitat is limited in the landscape and often fragmented.

Urbanization: Surviving populations within urban/suburban environments are more susceptible to extirpation because of increased recreational demands, changes in hydrology from flood control projects and road construction, competition from introduced weeds, and loss of native pollinators (Riedel 2002).

Road and Infrastructure Construction: Roads and structures built within Ute Ladies'-tresses habitat will directly disturb habitat and plants, and will indirectly impact populations by contributing to changes in hydrology (flooding or dewatering sites), favoring the establishment of competing weeds, create additional population fragmentation, and increase pollution runoff.

Recreation: Recreational activities can directly disturb habitat and plants. In Colorado the construction of hiking and biking trails is a threat to several populations. In Idaho, trampling and boat camping at fishing access sites has been reported as a potential threat. Also in Idaho, unauthorized off-road highway vehicle use is a potential threat.

Haying/Mowing is a threat to populations if not timed correctly. Mowing just before or during flowering can greatly reduce fruit production (Arft 1995).

Livestock Grazing is a threat to populations if not timed correctly. Ute Ladies'-tresses is edible to livestock. A reduction in flower and fruit production has been observed at sites that are grazed or trampled in the summer (Arft 1995, Fertig 2000, Murphy 2001).

STATE THREAT SCORE REASON
Reported threats to Montana's populations of Ute Ladies’-tresses focus primarily on potential impacts to the ephemeral wetland habitat for which it depends upon (MTNHP Threat Assessment 2021). Populations are found at the edges of wetlands, wet meadows, swales, and old meander channels that are outside of active stream channels. These habitats occur within land used for agriculture, ranching, and urban development/infrastructure and are prone to land use changes, livestock grazing, road construction and maintenance, and water management actions that modify seasonal hydrology. Reported threats inflicting direct stress are competition from invasive non-native species, urban development, damage from recreational use of off-highway vehicles (OHVs), and road construction. The risk of herbicide application and related decline in habitat quality is a concern as many populations exist on roadsides where herbicide is a common form of weed control. Certain agricultural and livestock grazing practices can be a threat if not managed or timed appropriately with Ute Ladies'-tresses' flowering and fruiting periods.