The United States, officially known as the United States of America or simply the US, is a country located in North America. It is divided into fifty states covering an area of 3,796,742 square miles with a population of 324 million, making it the 3rd largest country by land area and population. The country’s capital and largest cities are Washington D.C and New York respectively. The country’s ecology is megadiverse in that they harbor the majority of species found on the earth and a relevant number of endemic species. Over 17000 tall vascular plants and 1,800 species of flowering plants (angiosperms) are found in various states of the country but most are endangered due to the environmental, water, and air pollution.
Critically Endangered Plants Of The United States
Desert Yellowhead, scientifically known as the Yermo Xanthocephalus of the genus Yermo, is an endemic species which was discovered in 1991 in the mountainous parts of the western side of the United States. The plant is leafy with a height of approximately 12 inches and has flower heads which contain four to six yellow disk-shaped flowers. This plant has been listed as a threatened species due to human activities on the habitat in the two populations and also mining for minerals such as uranium which are radioactive minerals.
Persistent Trillium, scientifically known as the Trillium Persistens, is a North American species of the flowering plants.it was discovered in 1971 at only limited ranges throughout the United States. It is a herbaceous perennial plant that grows up to a height of approximately 12 inches, with a whorl alienation of leaves at the top of the stem below the flower. The flower has three petals which are less than an inch long.
Virginia Round-Leaf Birch
Virginia Round-Leaf Birch, scientifically known as Betula Uber is a rare species of tree in the birch family. It was discovered in 1918 but was believed to be extinct over time as it hadn’t been seen, but in 1975 few individual of the plant were found. It was listed as an endangered species then and conservation efforts begun like sprouting its seedlings in greenhouses, which evidenced the growing of 20 populations. The tree grows up to a height of 45 feet and is wind-pollinated with a lifespan of up to 50 years.
Capa Rose is a plant of the Verbenaceae family and is scientifically known as the Callicarpa ampla. It was discovered in 1827 and is a small evergreen tree or shrub which grows up to an approximate height of 49 feet. They have broad leafs which grow thinner towards the ends, with dark green color on the top and light green beneath. After pollination, the seeds formed are white in color but turns purple once ripen. It is found only in an elevated region of 3300 feet above sea level in Palo Colorado region, Puerto Rico.
Stern's Medlar, scientifically known as the Mespilus Canescens, was discovered in 1990 in the Prairie County, United States. The leaves of this tree are approximately 1 inch long with sparsely placed thorns and five-petal white flowers which appear during spring. With only 25 known plants, this endemic species is critically endangered but have been placed under the Konecny Grove Natural Area under protection.
Threats and Conservation Efforts
The native plants of the US are threatened by human activities and climate change and invasive plants. Invasive plants are non-native plants species whose introduction into the ecosystem cause harm to humans or to native plants. according to National Invasive Species Information Center (NISIC), the annual cost of controlling invasive plants species is $100 billion each year.