For example, its stout fibrous taproots restrict vegetative reproduction, and its slow growth gives it a disadvantage in competition with fast-growing plants, which can shade or crowd out the coneflower. The factors that adapt the Tennessee coneflower to a glade habitat may limit it elsewhere. Less than 6-8 in (15-20 cm) long are the most vulnerable during dry conditions. To survive in open glades, coneflowers must be able to compete successfully for scarce moisture, and drought places them under considerable stress. In summer, glade temperatures can be considerably hotter than in the surrounding forest. It is a harsh environment, with extremes in light, temperature, and moisture. The impenetrable bedrock often forces coneflower roots to grow horizontally. Tennessee purple coneflower grows in cedar glades, usually dominated by red cedar, in forest openings where bedrock is exposed or covered by a very thin layer of soil.
Flowers produce a small number of large seeds that do not adhere to animal fur and are not easily dispersed by common methods such as wind and water. Leaves grow from the base of the stem, which usually bears a single flower head.
Sharp-tipped bracts cause the flower to resemble a hedgehog, the Greek word for which, echinos, furnishes the genus name. Tennessee purple coneflower, Echinacea tennesseensis, normally grows 3 ft (0.9 m) or more in height and bears pale purple, ray flowers with a central disk, similar to daisies. Residential and commercial development competition. Pale purple, ray flowers with a central disk. The Tennessee coneflower was delisted effective September 2, 2011.Tennessee Purple Coneflower Echinacea tennesseensis Status The United States Fish and Wildlife Service proposed that this plant be removed from the endangered species list because all the former threats to the species are eliminated or reduced. The Tennessee coneflower was once a federally listed endangered plant species and its recovery has been aided by the purchase of habitat by the Nature Conservancy and the State of Tennessee. This isolation resulted in divergence and speciation of E. As conditions became wetter, the Echinacea populations became isolated on the prairie-like habitat of the cedar glades which were eventually surrounded by forest. It has been hypothesized that an ancestral Echinacea species spread into middle Tennessee during the hypsothermal period following the last ice age, when conditions were drier and prairies extended into much of the central eastern U.S.
Distribution Įchinacea tennesseensis is a rare species, found in fewer than 10 locations in Davidson, Wilson, and Rutherford Counties. angustifolia (widespread throughout the prairie of the central U.S.) and other common Echinacea species such as E. Ī noticeable characteristic is its generally erect ray flowers, in contrast to the more drooping rays of its most similar congener, E. The flowers are produced in a capitulum (flowerhead) up to 8 cm (3.2 inches) broad, with a ring of purple ray florets surrounding the brown disc florets. The leaves are hairy, lanceolate, and arranged in a basal whorl with only a few small leaves on the flower stems. Description Įchinacea tennesseensis is a herbaceous perennial plant growing to 75 centimetres (2.46 ft) tall. tennesseensis (Beadle) Binns, B.R.Baum & ArnasonĮchinacea tennesseensis, also known as the Tennessee coneflower or Tennessee purple coneflower, is a flowering plant in the family Asteraceae, endemic to the cedar glades of the central portion of the U.S.
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