Parish’s Daisy


Parish’s daisy, known by its scientific name Erigeron parishii as wellas by the moniker Parish’s fleabane, is a plant native to San Bernardino County and Riverside County. It is one of five federally-listed threatened species – along with the Cushenbury buckwheat, Cushenbury milk-vetch, San Bernardino Mountains bladderpd and Cushenbury Oxytheca – losing habitat to development and the limestone mining industry on the north slope of the San Bernardino Mountains. Of these five endangered plants, Parish’s daisy is the one that is yet most prolific, with the most numbers and a primary habitat that ranges some 35 miles long covering an estimated 1,029 acres in 50 separate enclaves stretching from San Bernardino County to Riverside County and in a smaller area in the hills around Yucca Valley. There are 16,000 known living Erigeron parishii plants occurring at elevations generally between 3,700 and 6,600 feet, most often in washes and canyon bottoms, but sometimes on alluvial benches or steep rocky mountainsides.
One factor in Erigeron parishii’s favor is it has a relatively high genetic diversity for a narrow endemic. Genetic diversity allows a living organism to adapt to changing environments. With more variation, it is more likely that some individuals in a population will possess variations in its genes that are suited for the environment.
Erigeron parishii is a small perennial herb reaching a maximum height of 12 inches. Its taproot can penetrate the carbonate soils to a depth of 20 inches. This gives the plant the ability to live in and on limestone. Its stem and foliage are covered in silvery-white hairs and most of the leaves are basal and measure from about one inch to less than two-and-a-half inches long.
The erect stems have inflorescences of one to ten flower heads, each between 0.4 inches to 0.8 inches) wide. The flower head has a center of golden yellow disc florets and a fringe of up to 55 lavender, pink, pale rose, or white ray florets, with 30-50 ray flowers per head.
Erigeron parishii usually grows on limestone substrates, or granite topped with a layer of limestone. It apparently requires very alkaline soils.
Parish’s daisy is a long-lived perennial that flowers from May through August, peaking mid-May to mid-June. Based on its conspicuous flowers, pollinators are insects including bees, butterflies and other known pollinators of similar and related species. Parish’s daisy produces plumed achenes adapted for wind dispersal and does not appear to have a seed dormancy mechanism. Based on observations of seedlings at several sites, reproduction is believed to be primarily by seed rather than vegetatively by rhizomes or stolons. There is no evidence of vegetative reproduction, and botanists have concluded that the species probably primarily reproduces sexually through outcrossing.
The same rock that the plant favors – limestone – is also sought after for human use and limestone mining is the most significant threat to its habitat. The primary threats to the plant associated with limestone mining are direct removal of mined materials which displaces the plant entirely, disposal of overburden on adjacent unmined habitat and road construction. Lesser threats include sand and gravel mining, off-highway vehicle use, recreational and urban development, powerline and hydroelectric development, and the loss of pollinators or seed dispersal agents.
Parish’s daisy was named by Asa Gray in 1884 in his Synoptical Flora of North America. It was reported to be “abundant on stony hillsides at Cushenberry Springs” by a botanist with the last name of Hall in 1907.

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