| Erigeron tweedyi | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Asterales |
| Family: | Asteraceae |
| Genus: | Erigeron |
| Species: | E. tweedyi |
| Binomial name | |
| Erigeron tweedyi | |
Erigeron tweedyi, or Tweedy's fleabane, is a perennial herb in the family Asteraceae. It is native to the Rocky Mountains in Montana, Idaho and Wyoming.
Erigeron tweedyi was described and published in 1888 by William Marriott Canby, who named it in honor of Frank Tweedy, the first to collect it. [1] Tweedy's specimen, the holotype, is deposited in Gray Herbarium at Harvard. [2]
Erigeron tweedyi is a low a perennial herb, to 20 cm tall, with a basal cluster of silvery hairy leaves. June through August, plants produce daisy-like flower heads to 1.5 cm across, with lavender rays surrounding yellow discs. [3] Plants grow from a taproot and branching underground caudex. Basal leaves are spoon-shaped to elliptic. The inflorescence is made up of 1-4 flower heads per stem. Each head contains 20–50 blue to purple (sometimes white) ray florets surrounding numerous yellow disc florets. [4]
Erigeron tweedyi is similar to E. tener in appearance, and the two sometimes grow in the same area. Differences are subtle. E. tweedyi has silvery basal leaves that are densely hairy, and 5-13 mm wide. In E. tener, basal leaves are gray green, less hairy, and narrower (2-7 mm); leaf tips are more sharply pointed. [5]
Erigeron tweedyi is endemic to southwest Montana, southern Idaho, and northwest Wyoming. [6] It grows on clay hills, rocky slopes, limestone talus, shale outcrops, and in sagebrush-grasslands, from valleys to subalpine, at 1600–3000 m elevation. [4] [7]
Erigeron tweedyi was first collected by Frank Tweedy in 1887, in rocky dry hills along Trail Creek in southwestern Montana. In his article about the new species, W.M. Canby noted: "It is a peculiar pleasure to give this plant the name of its discoverer, Mr. Frank Tweedy, author of an excellent catalogue of the 'Flora of Yellowstone Park.'" [1]
Tweedy's fleabane is cultivated in rock and alpine gardens. In keeping with its preferences in the wild, it does best on dry open to partially shaded sites. [8]
Erigeron concinnus, the Navajo fleabane, tidy fleabane or hairy daisy, is a perennial flowering plant in the family Asteraceae.
Erigeron coulteri is a species of flowering plant in the family Asteraceae known by the common names large mountain fleabane, Coulter's fleabane, and Coulter's daisy.
Erigeron eatonii is a North American species of flowering plants in the family Asteraceae known by the common name Eaton's fleabane.
Erigeron linearis is a species of flowering plant in the family Asteraceae known by the common name desert yellow fleabane or narrow leaved fleabane.
Erigeron petrophilus is a species of flowering plant in the family Asteraceae known by the common names rockloving erigeron or cliff fleabane. It is native to the mountain ranges of California from Siskiyou County south as far as San Luis Obispo County and El Dorado County. It also grows in southwestern Oregon.
Erigeron tener is a North American species of flowering plant in the family Asteraceae known by the common name slender fleabane. It is native to the western United States, largely in the Great Basin, in the states of California, Arizona, Nevada, Utah, Oregon, Wyoming, Idaho, and Montana.
Erigeron pumilus, the shaggy fleabane, or vernal daisy, is a hairy North American species of perennial plants in the family Asteraceae. It is widespread across much of western Canada and the western United States, from British Columbia east to Saskatchewan and south as far as Oklahoma and the San Bernardino Mountains of California. There have been reports of the plant growing in Yukon Territory, but these were based on misidentified specimens.
Erigeron evermannii is a North American species of flowering plants in the family Asteraceae known by the common name Evermann's fleabane.
Erigeron formosissimus is a North American species of flowering plants in the family Asteraceae known by the common name beautiful fleabane.
Erigeron glabellus is a North American species of flowering plants in the family Asteraceae, called the streamside fleabane.
Erigeron gracilis is a North American species of flowering plant in the family Asteraceae known by the common name quill fleabane.
Erigeron leiomerus is a rare species of flowering plant in the family Asteraceae known by the common names rockslide yellow fleabane or rockslide fleabane. It is native to the western United States, primarily in the Rocky Mountains and the Great Basin. It has been found in Montana, Idaho, Nevada, Utah, Wyoming, Colorado, and New Mexico.
Erigeron nanus is a North American species of flowering plant in the family Asteraceae known by the common name dwarf fleabane. It native to the western part of the United States, in Wyoming, northern Utah, southern Idaho, and northeastern Nevada.
Erigeron parryi is a species of flowering plant in the family Asteraceae known by the common name Parry's fleabane. It is native to the Rocky Mountains of southern Montana and northern Wyoming.
Erigeron radicatus is a North American species of flowering plant in the family Asteraceae known by the common names Hooker's fleabane and taproot fleabane The species grows in central Canada and parts of the north-central United States, primarily the northern Rocky Mountains and the Black Hills. It has been found in Idaho, Montana, Utah, Wyoming, Colorado, Nebraska, and South Dakota, with a few isolated populations reported from North Dakota.
Astragalus tweedyi, or Tweedy's milkvetch, is a perennial herb in the pea family. It is native to Washington and Oregon in the Pacific Northwest of the United States.
Plantago tweedyi, Tweedy's plantain, is a perennial herb in the plantain family. It is native to the western United States, from New Mexico and Arizona north to Montana.
Ivesia tweedyi, Tweedy's mousetail or Tweedy's ivesia, is a perennial herb in the rose family. It is native to the Pacific Northwest in the United States, from Washington east to westernmost Montana.
Chionophila tweedyi, or Tweedy's snowlover, is a perennial herb in the plantain family. It is native to Idaho and Montana in the western United States.
Calamagrostis tweedyi, the Cascade reedgrass or Tweedy's reedgrass, is a perennial in the grass family. It is native to the Pacific Northwest in the United States, in Washington, Oregon, Idaho, and Montana.