A cactus is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1,750 known species of the order Caryophyllales. The word cactus derives, through Latin, from the Ancient Greek word κάκτος (káktos), a name originally used by Theophrastus for a spiny plant whose identity is now not certain. Cacti occur in a wide range of shapes and sizes. They are native to the Americas, ranging from Patagonia in the south to parts of western Canada in the north, with the exception of Rhipsalis baccifera, which is also found in Africa and Sri Lanka. Cacti are adapted to live in very dry environments, including the Atacama Desert, one of the driest places on Earth. Because of this, cacti show many adaptations to conserve water. For example, almost all cacti are succulents, meaning they have thickened, fleshy parts adapted to store water. Unlike many other succulents, the stem is the only part of most cacti where this vital process takes place. Most species of cacti have lost true leaves, retaining only spines, which are highly modified leaves. As well as defending against herbivores, spines help prevent water loss by reducing air flow close to the cactus and providing some shade. In the absence of true leaves, cacti's enlarged stems carry out photosynthesis.
Euphorbia is a very large and diverse genus of flowering plants, commonly called spurge, in the family Euphorbiaceae. "Euphorbia" is sometimes used in ordinary English to collectively refer to all members of Euphorbiaceae, not just to members of the genus.
The poinsettia is a commercially important flowering plant species of the diverse spurge family Euphorbiaceae. Indigenous to Mexico and Central America, the poinsettia was first described by Europeans in 1834. It is particularly well known for its red and green foliage and is widely used in Christmas floral displays. It derives its common English name from Joel Roberts Poinsett, the first United States minister to Mexico, who is credited with introducing the plant to the US in the 1820s. Poinsettias are shrubs or small trees, with heights of 0.6 to 4 m. Though often stated to be highly toxic, the poinsettia is not dangerous to pets or children. Exposure to the plant, even consumption, most often results in no effect, though it can cause nausea, vomiting, or diarrhea.
Euphorbia tithymaloides is a perennial succulent spurge. An erect shrub, the plant is also known by the scientific name Pedilanthus tithymaloides. However, the genus Pedilanthus has been subsumed into the genus Euphorbia, and is more correctly known by its new name.
Euphorbia milii, the crown of thorns, Christ plant, or Christ's thorn, is a species of flowering plant in the spurge family Euphorbiaceae, native to Madagascar. The species name commemorates Baron Milius, once Governor of Réunion, who introduced the species to France in 1821.
Euphorbia albomarginata, whitemargin sandmat or rattlesnake weed, is a small low-growing perennial, in the spurge family native to desert, chaparral, and grassland habitats of southwestern North America, from southern and central California to Northern Mexico and Louisiana.
Euphorbia tirucalli is a tree native to Africa that grows in semi-arid tropical climates. A hydrocarbon plant, it produces a poisonous latex that can cause temporary blindness.
Curio rowleyanus, syn. Senecio rowleyanus, is a flowering plant in the daisy family Asteraceae. It is a creeping, perennial, succulent vine native to the Cape Provinces of South Africa. In its natural environment its stems trail on the ground, rooting where they touch and form dense mats. It often avoids direct sunlight by growing in the shade of other plants and rocks. It is commonly known as string-of-pearls or string-of-beads.
Euphorbia corollata is an herbaceous perennial plant in the family Euphorbiaceae that is native to North America. A common name for the species is flowering spurge. It has a milky sap that can cause skin and eye irritation in some people. It grows up to 1 m (3 ft) tall, with smooth stems and light green leaves arranged alternately or in whorls. Leaves are about 10 mm wide and 75 mm (3 in) long. Each stem terminates in a panicle 20 to 25 mm across. Flowers are about 6 mm across and consist of one pistillate and several staminate flowers surrounded by five white bracts - not petals but formed from the involucre at the base of the flowers. Flowering spurge blooms from June to September.
Euphorbia misera is a semi-succulent shrub in the genus Euphorbia commonly known as the cliff spurge or coast spurge. A drought-deciduous shrub, it is typically found as a gnarled, straggly plant occupying seashore bluffs, hills and deserts. Like other members of its genus, it has a milky sap, which can be found exuding out of the light gray bark when damaged. The alternately-arranged leaves are round and folded in the middle, with small hairs on them. The "flowers" can be found blooming year-round, and are colored maroon or yellow in the center with 5 white to light-yellow petal-like appendages attached outside. This species is native to the Baja California peninsula and Sonora in Mexico, and the coast of southern California in the United States, where it is a rare species. It is threatened in some localities by the development of its coastal habitat, which tends to be prime locations for high-end residential and commercial developments.
Euphorbia ingens is a species of flowering plant in the family Euphorbiaceae. It is native to dry areas of southern Africa. It is popularly known as the candelabra tree or naboom. Its milky latex can be extremely poisonous and is a dangerous irritant.
Euphorbia balsamifera is a flowering plant in the spurge family Euphorbiaceae. It is distributed in the Canary Islands and the western Sahara. It is the vegetable symbol of the island of Lanzarote. Euphorbia adenensis has been treated as a subspecies of this species.
Aloe petricola belongs to the genus Aloe in the family Asphodelaceae, and is commonly known as a stone aloe. This particular aloe is a flowering species with unique and distinct inflorescences, which make the plant easy to identify and distinguish from other Aloe plants. Aloe petricola is very popular for gardening because of its beautiful and radiant colors. Like many Aloe species, Aloe petricola is used for medical purposes, as it aids in healing wounds and minor burns.
Euphorbia royleana is a species of flowering plant in the family Euphorbiaceae. It is also known as Sullu spurge, and Royle's spurge. It is a succulent and almost cactus like in appearance although unrelated. It grows right across the Himalaya mountains from Pakistan, India, Bhutan, Myanmar, Nepal to western China. It prefers dry and rocky slopes between 1000 and 1500 meters, but has been found up to 2000 meters. Flowering and fruiting is in spring to early summer (March–July) and seeding is in June–October. It is used as a hedging plant in northern India and has medicinal uses.
Crassula ovata, commonly known as jade plant, lucky plant, money plant or money tree, is a succulent plant with small pink or white flowers that is native to the KwaZulu-Natal and Eastern Cape provinces of South Africa, and Mozambique; it is common as a houseplant worldwide. Much of its popularity stems from the low levels of care needed; the jade plant requires little water and can survive in most indoor conditions. It is sometimes referred to as the money tree; however, Pachira aquatica also has this nickname.
Crotalaria retusa is a species of flowering plant in the legume family known by various common names including devil-bean, rattleweed, shack shack, and wedge-leaf rattlepod. It is poisonous to livestock, and contaminates human food. Its original native range is unclear, probably including tropical Asia, Africa and Australia. It has been introduced as a crop plant in many tropical areas and has escaped from cultivation to become a troublesome weed; it is listed as a noxious weed in several US states, Puerto Rico, the Virgin Islands, and is listed as an invasive weed in India, Cuba, and Cocos Island. Unlike some other species of Crotalaria, it is an annual plant.
Euphorbia abyssinica, commonly known as the desert candle or candelabra spurge, is a species of plant in the family Euphorbiaceae. E. abyssinica is endemic to Ethiopia, Somalia, Sudan and Eritrea. It was first described in 1791, by the German botanist Johann Friedrich Gmelin. In its native habitat, it can grow up to 10 m (33 ft) tall. The woody stem is used for firewood and as timber in roofing, furniture and other items, and the sap is used in traditional medicine. It is also cultivated as an ornamental house plant.
Euphorbia rhombifolia is a species of flowering plant in the Euphorbiaceae family. It is native to Namibia and South Africa, where it is widespread in clay-rich soils, extending as far east as Kwazulu-Natal.
Euphorbia caducifolia is a subtropical succulent species of flowering plant in the family Euphorbiaceae. It is found in the arid regions of northwestern Indian subcontinent. In India it is known as the leafless milk hedge.
Euphorbia nivulia is a subtropical succulent species of flowering plant in the family Euphorbiaceae. It is found in the Indian subcontinent and is commonly known as the leafy milk hedge, holy milk hedge or dog's tongue.
