An achene, also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate and indehiscent. Achenes contain a single seed that nearly fills the pericarp, but does not adhere to it. In many species, what is called the "seed" is an achene, a fruit containing the seed. The seed-like appearance is owed to the hardening of the fruit wall (pericarp), which encloses the solitary seed so closely as to seem like a seed coat.
Carex is a vast genus of more than 2,000 species of grass-like plants in the family Cyperaceae, commonly known as sedges. Other members of the family Cyperaceae are also called sedges, however those of genus Carex may be called true sedges, and it is the most species-rich genus in the family. The study of Carex is known as caricology.
Carex jamesii, known as James's sedge or grass sedge, is a species of sedge native to North America from Minnesota east to New York and south to Oklahoma and South Carolina. It occurs in mesic hardwood forests and produces fruits from early May to mid July. It has two to four perigynia that are subtended by leaf-like pistillate scales. Its seeds are dispersed by ants.
In botany, a diaspore is a plant dispersal unit consisting of a seed or spore plus any additional tissues that assist dispersal. In some seed plants, the diaspore is a seed and fruit together, or a seed and elaiosome. In a few seed plants, the diaspore is most or all of the plant, and is known as a tumbleweed.
Carex heteroneura is a species of sedge known by the common name different-nerve sedge. It is native to western Canada and the western United States, where it grows in moist mountain habitat such as forests and meadows.
Carex klamathensis is a rare species of sedge known by the common name Klamath sedge. It is known from 15 or fewer populations in southern Oregon and three populations in the Klamath Region of northern California. It was described to science only in 2007. Its habitat includes fens and other wet habitat, on serpentine soils. It was discovered independently by botanists Peter Zika and Lawrence Janeway.
Carex binervis, the green-ribbed sedge, is a European species of sedge with an Atlantic distribution. It is found from Fennoscandia to the Iberian Peninsula, and occurs in heaths, moorland and other damp, acidic environments. It typically grows to a height of 15–120 cm (6–50 in), and has inflorescences comprising one male and several female spikes, each up to 45 mm (1.8 in) long. The utricles have two conspicuous green veins, which give rise to both the scientific name and the common name of the species. In the vegetative state, it closely resembles C. bigelowii, a species that usually grows at higher altitude. C. binervis was first described by James Edward Smith in 1800, and is classified in Carex sect. Spirostachyae; several hybrids with other Carex species are known.
Carex distans, commonly known as distant sedge, is a plant species in the sedge family, Cyperaceae. It is native to Europe and North Africa. It is part of a complex of similar species that occur across Eurasia. Its relatives include Carex diluta of central Asia, which has also introduced to North America in Montana. C. distans has been introduced to US states including Maryland and Pennsylvania. More recently, it was found in Oregon. There is a report from Victoria, Australia as well.
Carex lacustris, known as lake sedge, is a tufted grass-like perennial of the sedge family (Cyperaceae), native to southern Canada and the northern United States. C. lacustris us an herbaceous surface-piercing plant that grows in water up to 50 cm (1.6 ft) deep, and grows 50–150 cm (1.6–4.9 ft) tall. It grows well in marshes and swampy woods of the boreal forest, along river and lake shores, in ditches, marshes, swamps, and other wetland habitat. It grows on muck, sedge peat, wet sand or silt, in filtered or full sunlight.
Carex porrecta is a plant species known from Costa Rica, Colombia, Venezuela and Ecuador. It is found in humid forests at elevations of 1,600–2,600 metres (5,200–8,500 ft).
Carex kobomugi is a species of sedge, known as the Japanese sedge or Asiatic sand sedge, that lives in sandy coastal areas of eastern Asia, and has become an invasive species in the north-eastern United States.
Carex rosea, the rosy sedge, is a flowering plant and part of the family Cyperaceae. Synonyms for Carex rosea include Carex concoluta, and Carex flaccidula. It is native to central and eastern North America and it exists in wet to dry soils. Carex rosea can be found in shores of streams and bottomlands, as well as ponds. It is known to have good adaptations to dry-shade locations. It is an evergreen plant which is easy to grow.
Carex davisii, known as Davis' sedge or awned graceful sedge, is a species of Carex native to North America. It is listed as an endangered, threatened, or species of concern across much of edge of its range. It was named in the 1820s by Lewis David de Schweinitz and John Torrey in honor of Emerson Davis (1798–1866), a Massachusetts educator and "enthusiastic student of the genus" Carex.
Carex brevior, known as shortbeak sedge and plains oval sedge, is a species of sedge native to North America. The specific epithet brevior means "shorter" in Latin.
Carex arctogena is a member of the sedge family (Cyperaceae) which grows in high alpine areas. It is one of the few "bipolar" species; it has populations in Greenland, Scandinavia, Russia, Canada and southern South America. Plants in the far north and south appear to be genetically identical, having taken advantage of a similar niches on opposite ends of the globe.
Carex amphibola, known as gray sedge, is a species of flowering plant in the family Cyperaceae. It was first formally named in 1855. Carex amphibola is native to the eastern United States and Canada.
Carex pedunculata, the long-stalk sedge or longstalk sedge, is a species of flowering plant in the genus Carex, native to Canada and the central and eastern United States. Its seeds are dispersed by ants.
Carex muehlenbergii is a species of flowering plant, it is a type of sedge. It is a grass-like plant in the family Cyperaceae. Its common names include sand sedge, Muhlenberg's sedge.
Carex parva, also known to Chinese people as xiao tai cao, is a tussock-forming species of perennial sedge in the family Cyperaceae. It is native to parts of Asia from Afghanistan to Mongolia.
Carex buxbaumii (green perigynia in center and on right, with dark brown scales)
Carex melanostachya (scale on left, perigynium on right)
Carex michelii (scale on left, perigynium on right)
Carex hirta perigynia
