Plants named in 1800

Horseradish (Armoracia rusticana, syn. Cochlearia armoracia) is a perennial plant of the family Brassicaceae (which also includes mustard, wasabi, broccoli, cabbage, and radish). It is a root vegetable, cultivated and used worldwide as a spice and as a condiment. The species is likely native to Southeastern Europe and Western Asia.

Aegle marmelos, commonly known as bael (a.k.a. bel, beli, or bhel), also Bengal quince, golden apple, Japanese bitter orange, stone apple or wood apple, is a species of tree native to the Indian subcontinent and Southeast Asia. It is present in India, Pakistan, Bangladesh, Sri Lanka, and Nepal as a naturalized species. The tree is considered to be sacred by Hindus and Buddhists. Bael is the only member of the monotypic genus Aegle.

Persicaria hydropiper (syn. Polygonum hydropiper), also known as water pepper, marshpepper knotweed, arse smart or tade, is a plant of the family Polygonaceae. A widespread species, Persicaria hydropiper is found in Australia, New Zealand, temperate Asia, Europe and North America. The plant grows in damp places and shallow water. Cultivated varieties are eaten in East Asia for their pungent flavor.

Centaurium erythraea is a species of flowering plant in the gentian family known by the names common centaury and European centaury. It is also commonly known as feverfoullie, gentian or centaury.

Bistorta officinalis (synonym Persicaria bistorta), known as bistort, common bistort, European bistort, or meadow bistort, is a species of flowering plant in the dock family Polygonaceae native to Europe and northern and western Asia. Other common names include snakeroot, snake-root, snakeweed, and Easter-ledges.

Eucalyptus globulus, commonly known as southern blue gum or blue gum, is a species of flowering plant in the family Myrtaceae. It is a tall, evergreen tree endemic to southeastern Australia. This Eucalyptus species has mostly smooth bark, juvenile leaves that are whitish and waxy on the lower surface, glossy green, lance-shaped adult leaves, glaucous, ribbed flower buds arranged singly or in groups of three or seven in leaf axils, white flowers and woody fruit. There are four subspecies, each with a different distribution across Australia, occurring in New South Wales, Victoria and Tasmania.

Oncidium is a genus of about 370 species of orchid in the family Orchidaceae. It is distributed across tropical and subtropical America from Mexico, Central America and the West Indies to northern Argentina, with one species (O. ensatum) extending into Florida. Common names for plants in this genus include dancing-lady orchid. A molecular phylogenetic study published in 2009 labeled the Oncidium alliance "grossly polyphyletic." In the same year, the American Orchid Society labeled the genus a "dumping ground". A consensus announced in April 2013 resulted in major taxonomic changes to

Armoracia is a genus of flowering plants of the family Brassicaceae, native to the Palaearctic. Its best known member is horseradish, Armoracia rusticana, which is the type species.

Cymbalaria muralis, commonly called ivy-leaved toadflax, is a low, spreading, trailing plant with small purple flowers, native to rocky habitats in southern Europe. It belongs to the plantain family (Plantaginaceae), and is introduced and naturalised in many other temperate locations. The flower stalk is unusual for seeking light until it is fertilized, after which it grows away from the light. Other names include coliseum ivy, Kenilworth ivy, mother of thousands, Oxford ivy, and wandering sailor.

Persicaria amphibia (syn. Polygonum amphibium) is a species of flowering plant in the knotweed family known by several common names, including longroot smartweed, water knotweed, water smartweed, and amphibious bistort. It is native to much of North America, Asia, Europe, and parts of Africa, and it grows elsewhere as an introduced species and sometimes a noxious weed.

Caladium is a genus of flowering plants in the family Araceae. They are often known by the common name elephant ear (which they share with the closely related genera Alocasia, Colocasia, and Xanthosoma), heart of Jesus, and angel wings. There are over 1000 named cultivars of Caladium bicolor from the original South American plant. The genus Caladium includes seven species that are native to South America and Central America, and naturalized in India, parts of Africa, and various tropical islands. They grow in open areas of the forest and on the banks of rivers and go dormant during the dry

Arctium minus, commonly known as lesser burdock, little burdock, louse-bur, common burdock, button-bur, cuckoo-button, or wild rhubarb, is a biennial plant native to Europe.

Bistorta vivipara (synonym Persicaria vivipara) is a perennial herbaceous flowering plant in the knotweed and buckwheat family Polygonaceae, commonly known as alpine bistort. Scientific synonyms include Bistorta vivipara and Polygonum viviparum. It is common all over the high Arctic through Europe, North America, incl. Greenland, and temperate and tropical Asia. Its range stretches further south in high mountainous areas such as the Alps, Carpathians, Pyrenees, Caucasus, Alaska and the Tibetan Plateau.

Persicaria lapathifolia (syn. Polygonum lapathifolium), known as pale persicaria, is a plant of the family Polygonaceae. It is considered to be native throughout most of the world, from arctic to tropical realms, except South America and Southern Africa. It is closely related to Persicaria maculosa and as such is considered a weed in Britain and Europe. Other common names for the plant include pale smartweed, curlytop knotweed, and willow weed. It is a species complex made up of a great many varying forms, sometimes considered varieties. The environment also has a strong influence on the

Arenga is a genus of palms, native to Southeast Asia, southern China, New Guinea, and northern Australia. They are small to medium-sized palms, growing to 2–20 m tall, with pinnate leaves 2–12 m long. Arenga palms can grow in areas with little sunlight and relatively infertile soil.

Pulicaria dysenterica, the common fleabane, or, in North America, meadow false fleabane, is a species of fleabane in the family Asteraceae. It is native to Europe and western Asia where it grows in a variety of habitats ranging from semi-arid Mediterranean woodlands to wetter situations. Pulicaria dysenterica is perennial and can form dense clusters of plants, spreading by its roots. It flowers at its maximum height of about 60 centimetres (2.0 ft). Leaves are alternately arranged and clasp the stem, which itself contains a salty-astringent liquid. The yellow inflorescences are typically

Malaxis monophyllos, the white adder's mouth, is a terrestrial species of orchid. It is widespread across much of Europe (Germany, Italy, Poland, Scandinavia, Ukraine, etc.), Asia (China, Japan, Russia, Nepal, Philippines, etc.), and much of southern Canada. In the United States, it grows mostly in southern Alaska, New England and the Great Lakes region, with isolated populations reported from Colorado and California.

Lathyrus vernus, the spring vetchling, spring pea, or spring vetch, is a species of flowering herbaceous perennial plant in the genus Lathyrus, native to forests of Europe and Siberia. It forms a dense clump of pointed leaves with purple flowers in spring, shading to a greenish-blue with age. This species, and the cultivar 'Alboroseus', have gained the Royal Horticultural Society's Award of Garden Merit.

Viscaria vulgaris, the sticky catchfly or clammy campion, is a flowering plant in the family Caryophyllaceae. It is an upright perennial growing to 60 cm (24 in) in height. The leaves are lanceolate. The flowers, which are 20 mm across and bright rosy-pink, appear in long whorled spikes from May to August. It grows on cliffs and rocky places. In Central Europe, Lychnis viscaria can be found in a variety of habitats, such as dry meadows, lush grasslands, stony slopes, rocky outcrops of hilly terrain, and open or sparse canopied forests. It has taken over vineyards and roadside vegetation, and

Lathyrus niger, also known as black pea, blackening flat pea and black bitter vetch, is a perennial legume that is native to Europe. Its common name is reference to the blackening of the plant's foliage as it dies. The seeds of the species are not to be confused with edible 'black peas', which are a form of Pisum sativum. Seeds of Lathyrus species are toxic, containing an enzyme that interferes with collagen synthesis to cause the disease Lathyrism.

The American chestnut (Castanea dentata) is a large, fast-growing deciduous tree of the beech family native to eastern North America. As is true of all species in the genus Castanea, the American chestnut produces burred fruit with edible nuts. The American chestnut was once common in the Appalachian Mountain range and was a dominant species in the oak-chestnut forest region of its central and southern range. During the early to mid-20th century, American chestnut trees were devastated by chestnut blight, a fungal disease that came from Japanese chestnut trees that were introduced into North

Eriophorum latifolium, commonly known as broad-leaved bog-cotton and broad leaved cotton grass is a species of flowering plant belonging to the family Cyperaceae.

Pulsatilla alpina, the alpine pasqueflower or alpine anemone, is a species of flowering plant in the family Ranunculaceae, native to the mountain ranges of central and southern Europe, from central Spain to Croatia. It is an herbaceous perennial growing to 15–30 cm (6–12 in) tall by 20 cm (8 in) wide, and can be found at altitudes of 1,200–2,700 m (3,900–8,900 ft).

Falcaria vulgaris, the sickleweed or longleaf, is the sole species in the genus Falcaria. It is a biennial herb of the spherical shape. Blossoms in June–July. Grows in Europe, Siberia, Middle East, Northern Africa, North and South Americas. Contains alkaloids, carotene, vitamin C, proteins. Its use as an alternative medicine may offer several advantages, especially in the treatment of stomach and skin ulcers, diabetes, infections, and liver and kidney disorders.

Rosa tomentosa, otherwise known as the harsh downy-rose, is a species of wild rose. It is a shrub growing to about 3 metres (10 ft). It is found in Asia Minor, the Caucasus (where it may not be native), and much of Europe: the British Isles, France, Central Europe, northern Spain, Italy, and the Balkans (except Greece). On the British Isles it can be found in hedgerows and woodland margins, and it typically flowers between June and July. Further south, in Bulgaria, it flowers in May.

Epipactis microphylla, the small-leaved helleborine, is a species of orchid. It is native to much of Europe and to Southwest Asia as far east as Iran though noticeably absent from the British Isles and from Scandinavia. It has also been found in North Africa, in the Babor mountains in Little Kabylia, Algeria.

Carex davalliana, or Davall's sedge, is a species of sedge found in inland wetlands across continental Europe. It is dioecious, with male and female flowers on separate plants.

Senecio vernalis is one of the European species of Senecio, an annual that is also known as eastern groundsel. While it has been long classified as Senecio vernalis, this species has more recently been described as a subspecies of Senecio leucanthemifolius and is now included by some in that species.

Rumex palustris, or marsh dock, is a plant species of the genus Rumex, found in Europe. The species is a dicot belonging to the family Polygonaceae. The species epithet palustris is Latin for "of the marsh" which indicates its common habitat.

Ophrys speculum, the mirror orchid, is a species of Ophrys distributed throughout the Mediterranean that is pollinated exclusively by a single species of scoliid wasp.