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What Are the Top Ten Endangered Plants?

A lot of attention is given to endangered species. Most of that attention is focused on animals, but there are just as many plants that are critically endangered, if not more. Those plants span the globe and consist of flowers, vines, shrubs, trees, herbs and more. Some plants appear similar to their common relatives, while others are unique. In the interests of ecological diversity, efforts are being made to save these and other endangered plants.

Western Prairie Fringed Orchid

The western prairie fringed orchid (Platanthera praeclara) exists only in five Midwestern states of the U.S. The Endangered Species Coalition estimates that there are 172 populations of this plant, only four of which have more than 1,000 plants. It is a wetland plant that grows in areas known as "prairie potholes," indentations left by glacier activity in the most recent ice age, about 20,000 years ago. The major causes of the decline of this plant are considered development of their habitat, overgrazing, fires and global warming.

Rafflesia Flower

The Rafflesia Flower (Rafflesia arnoldii) is thought to be the largest flower on the planet. The flower, which lacks a stem, leaves or even a root system, has a pungent odor reminiscent of rotting flesh. It grows to an astounding 3 feet in diameter and weights as much as 24 pounds. A parasitic plant that grows only on the Tetrastigma vine, the Rafflesia is native only to the forests of Borneo and Sumatra. It is unclear how many of these plants exist in the wild.

Georgia Aster

The Georgia Aster (Symphyotrichum georgianum) is native to the southeastern United States. Originally grown in only a few small pockets, there are an estimated 60 populations of this plant in existence due to the development of their natural habitats, according to, a nonprofit conservation organization.

Wiggin's Acalypha

Wiggin's Acalpypha (Acalypha wigginsii) is native to only one small part of the Galapagos Islands. Construction and loss of their habitat has led those herbaceous plants to dwindle in number. They are considered critically endangered, according to the Galapagos Conservation Trust.

Texas Wild Rice

With just about 140 clumps of this plant left, things seem grim for Texas Wild Rice (Zizania texana). Endemic only to the fresh water of the San Marcos River, this plant is threatened by low water levels in the river caused by nearby Spring Lake dam, according to the Center for Plant Conservation.

Howell's Spectacular Thelypody

Howell's Spectacular Thelypody (Thelypodium howellii ssp. spectabilis) has only five existing populations left in the world, all of which are on private land in northeastern Oregon. As of 1999, only 30,000 plants remained, dwindling each year due to excessive mowing of the grassy areas that this biennial plant call their home, according to the Center for Plant Conservation.

Stenogyne kanehoana

A plant that was thought to be extinct until the emergence of one plant in 2000, Stenogyne kanehoana is found only in the Waianae Mountains of Oahu, Hawaii. It is a climbing vine of the mint family with dense, hairy leaves. As of 2001, cuttings of the plant were grown with some success in captivity at the Lyon Arboretum, according to the Center for Plant Conservation.

Ouachita Mountain Goldenrod

Solidago ouachitensis, or Ouachita Mountain Goldenrod, is found in only three counties on the Arkansas and Oklahoma border. The exact surviving number of these plants is unknown, but they are thought to be leftovers from the last ice age, preferring to grow only in the cool, moist ridges of the Ouachita Mountains.


The population of enrubio (Solanum drymophilum) numbered a mere 150 individual plants when surveyed in 1992. Endemic to Puerto Rico, this miniscule shrub with sharp spines is under direct threat of being devastated due to concerns that it is harmful to grazing farm animals.

Arizona Agave

Less than 100 Arizona Agave plants, Agave arizonica, existed when they were surveyed in 1984. That number has not changed significantly since then. Only two populations exist, both in Tonto National Forest of Arizona. Within that forest, the New River Mountains and the Sierra Ancha Mountains are considered the only habitats of this rare agave, according to the Center for Plant Conservation.

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