''Echinacea tennesseensis'', also known as the Tennessee coneflower or Tennessee purple coneflower, is a

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

in the family

Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the cedar glades of the central portion of the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its so ...

Tennessee Tennessee (, ), officially the State of Tennessee, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Kentucky to the north, Virginia to the northeast, North Carolina t ...

Description

''Echinacea tennesseensis'' is a

herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of ...

perennial plant In horticulture, the term perennial (''wikt:per-#Prefix, per-'' + ''wikt:-ennial#Suffix, -ennial'', "through the year") is used to differentiate a plant from shorter-lived annual plant, annuals and biennial plant, biennials. It has thus been d ...

growing to tall. The

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

are hairy, lanceolate, and arranged in a basal whorl with only a few small leaves on the flower stems.Flora of North America, ''Echinacea tennesseensis'' (Beadle) Small, 1933. Tennessee purple coneflower
/ref> The

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

s are produced in a capitulum (flowerhead) up to 8 cm (3.2 inches) broad, with a ring of purple ray

florets This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary ...

surrounding the brown disc florets. A noticeable characteristic is its generally erect ray flowers, in contrast to the more drooping rays of its most similar congener, '' E. angustifolia'' (widespread throughout the

prairie Prairies are ecosystems considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and a composition of grasses, herbs, and shrubs, rather than trees, as the ...

of the central U.S.) and other common ''Echinacea'' species such as '' E. purpurea''.

Distribution

''Echinacea tennesseensis'' is a rare species, found in fewer than 10 locations in Davidson, Wilson, and Rutherford Counties. Echinacea tennesseensis JBM

It has been hypothesized that an ancestral ''Echinacea'' species spread into middle Tennessee during the hypsithermal period following the last ice age, when conditions were drier and prairies extended into much of the central eastern U.S. that is now forested. As conditions became wetter, the ''Echinacea'' populations became isolated on the prairie-like habitat of the cedar glades which were eventually surrounded by forest. This isolation resulted in divergence and speciation of ''E. tennesseensis''.

Conservation status

The Tennessee coneflower was once a federally listed endangered plant species and its recovery has been aided by the purchase of

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

the Nature Conservancy The Nature Conservancy (TNC) is a global environmental organization headquartered in Arlington, Virginia, United States. it works via affiliates or branches in 79 countries and territories, as well as across every state in the US. Founded in ...

and the State of Tennessee. The

United States Fish and Wildlife Service The United States Fish and Wildlife Service (USFWS or FWS) is a List of federal agencies in the United States, U.S. federal government agency within the United States Department of the Interior which oversees the management of fish, wildlife, ...

proposed that this plant be removed from the endangered species list because all the former threats to the species are eliminated or reduced.USFWS
Removing the Tennessee Purple Coneflower From the Federal List of Endangered and Threatened Plants.
''Federal Register'' August 12, 2010. The Tennessee coneflower was delisted effective September 2, 2011.

References

External links

{{Taxonbar, from=Q5332437 tennesseensis Flora of Tennessee Endemic flora of the United States Endangered flora of the United States Plants described in 1898