Frasera paniculata
| Frasera paniculata | |
|---|---|
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| Frasera paniculata close-up of flowers | |
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| Frasera paniculata (note the paniculate inflorescence) | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Embryophytes |
| Clade: | Tracheophytes |
| Clade: | Spermatophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Gentianales |
| Family: | Gentianaceae |
| Genus: | Frasera |
| Species: | F. paniculata |
| Binomial name | |
| Frasera paniculata | |
| Synonyms | |
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Frasera paniculata, commonly known as the tufted green gentian, tufted elkweed, or tufted frasera, is a species of flowering plant in the gentian family, Gentianaceae. It is a short-lived biennial or perennial herb native to the Four Corners region of the southwestern United States. Its range includes Arizona, Colorado, New Mexico, and Utah, where it grows in open shrublands, desert vegetation, pinyon–juniper woodlands, sandy flats, and areas of exposed rock.[2][1]
The species produces a basal rosette of long, narrow leaves and generally a single tall flowering stem bearing a branched panicle of greenish-white, dark-spotted flowers.[3]
Description
[edit]Frasera paniculata is a biennial or short-lived perennial herb arising from a thickened taproot and enlarged caudex. It usually produces a single stout stem, although more than one stem may occasionally develop..[3][1]
The leaves are concentrated in a basal rosette. They are linear-lanceolate to lanceolate. Their margins are white and often wavy. Stem leaves are absent or few, oppositely arranged, and become progressively smaller toward the inflorescence, where they are reduced to small bracts.[3]
The inflorescence is a mostly leafless, branched panicle. The flowers are borne on short stalks and are usually arranged in groups of two to four at each node.[3]
The flowers are four-parted. The four sepals are lanceolate to ovate, often white-margined. The four petals are oblanceolate, greenish white, and marked with dark dots.[3]
The corolla bears a weakly developed corona consisting of only a few hairs or none. Each petal contains a rounded or elliptic nectar pit. The pit has two basal tubes whose openings are fringed. The margins of the nectar glands may be hairy or hairless.[3]
The pistil is sessile. The mature fruit is a capsule with the style persisting at its tip. The seeds are dark brown, flattened, wingless, and irregularly rectangular. They have a roughened surface.[3]
Flowering generally occurs from May through July, and fruiting from June through August.[1] [3]
Taxonomy
[edit]Frasera paniculata was described by American botanist John Torrey in 1857. The name was published in a botanical report prepared as part of the United States Pacific railroad surveys.[4]
The name is cited as:
- Frasera paniculata Torr., Pacif. Railr. Rep. 4(5, 4): 126. 1857.[4]
NatureServe reports that the type collection was made in 1853 at Inscription Rock, now within El Morro National Monument in New Mexico.[1]
Plants of the World Online accepts Frasera paniculata as a distinct species.[2] Its listed synonyms include:
- Swertia bigelowii Kuntze
- Frasera utahensis M.E.Jones
- Leucocraspedum utahense (M.E.Jones) Rydb.
- Swertia utahensis (M.E.Jones) H.St.John[2]
The specific epithet paniculata refers to the species' branched, paniculate inflorescence.
Distribution
[edit]Frasera paniculata is endemic to the United States and occurs in the Four Corners region. It is most frequent in southeastern Utah and also occurs in northern Arizona, northwestern New Mexico, and western Colorado.[1]
NatureServe estimates its total range extent at approximately 143,000 km2 (55,000 sq mi). The species has an estimated area of occupancy of approximately 320 km2 (120 sq mi).[1]
Habitat and ecology
[edit]Frasera paniculata grows in dry, open habitats on sandy, silty, or clay soils and on exposed slickrock. Vegetation types include open shrublands, salt-desert shrub, warm-desert shrub, and pinyon–juniper woodland.[1]
It occasionally occurs in lower-elevation springs and hanging gardens, although these are less typical habitats. [3][1]
The species is biennial or a short-lived perennial. Individual plants may remain vegetative as basal rosettes before producing a tall flowering stalk. After flowering and fruiting, at least some individuals likely die, although the duration of the life cycle may vary with environmental conditions.
Conservation
[edit]NatureServe classifies Frasera paniculata as G4, or apparently secure, globally. It is also ranked N4 in the United States. State conservation ranks are S3 in Arizona, S1 in Colorado, S3 in New Mexico, and S2S3 in Utah. It has no status under the United States Endangered Species Act.[1]
The global rank was reviewed on 22 August 2023 using NatureServe's conservation-rank calculator.[1]
NatureServe estimates that there are approximately 80 occurrences across the species' range, with a plausible range of between 21 and 300 occurrences. Many populations occur on protected or otherwise managed public lands.[1]
Protected occurrences are known from Kaibab National Forest, Grand Canyon National Park, Petrified Forest National Park, Canyon de Chelly National Monument, and Vermilion Cliffs National Monument in Arizona. In Utah, the species occurs in Arches National Park, Glen Canyon National Recreation Area, Natural Bridges National Monument, Grand Staircase–Escalante National Monument, and Red Cliffs State Park. Additional occurrences are found on lands managed by the Bureau of Land Management.[1]
NatureServe considers the overall degree of threat to be low. Potential threats include livestock grazing, recreational disturbance—particularly from off-highway vehicles—and severe or prolonged drought. Climate change may intensify drought-related impacts within the species' arid and semiarid habitat.[1]
References
[edit]- 1 2 3 4 5 6 7 8 9 10 11 12 13 14 "Frasera paniculata". NatureServe Explorer. NatureServe. Retrieved 21 July 2026.
- 1 2 3 "Frasera paniculata Torr". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 21 July 2026.
- 1 2 3 4 5 6 7 8 9 "Frasera paniculata". SEINet: Arizona–New Mexico Chapter. Symbiota. Retrieved 21 July 2026.
- 1 2 "Frasera paniculata Torr". International Plant Names Index. Royal Botanic Gardens, Kew; Harvard University Herbaria & Libraries; Australian National Herbarium. Retrieved 21 July 2026.