The morning-glory family
Before dealing with the morning-glory family in depth, a selection of photographs shows the variation within this family.
Glorious pink morning-glory (Ipomoea carnea) in morning light, Kerala, India. The specific name carnea is from the Latin carnes, meaning meat, referring to the flesh-coloured flowers of this species. Occasionally, though, it has whitish flowers, as in these pictures. (Photos copyright © by Kaj Halberg)
Railroad creeper (Ipomoea cairica), enveloping a growth of dwarf bamboo, Taichung, Taiwan. (Photo copyright © by Kaj Halberg)
The flowers of field bindweed (Convolvulus arvensis) are usually white, or white with pink markings, but a rose-coloured variety is not uncommon. This one was photographed on the island of Bornholm, Denmark. (Photo copyright © by Kaj Halberg)
A species of morning-glory of the genus Astripomoea, growing on a savanna in Tarangire National Park (top) and near Mkomazi National Park, both in northern Tanzania. (Photos copyright © by Kaj Halberg)
This parasitic giant Asian dodder (Cuscuta reflexa) has completely enveloped a bush at Angkor Wat, Cambodia. (Photos copyright © by Kaj Halberg)
Raindrops cling to flowers of a species of morning-glory, Ipomoea imperati, shortly after a shower, Tortuguero National Park, Limón, Costa Rica. (Photo copyright © by Kaj Halberg)
The genus Evolvulus, dwarf morning-glories, contains about a hundred species, with the highest concentration in the Americas. This picture shows slender dwarf morning-glory (Evolvulus alsinoides), which is distributed in most warmer areas of the world, here photographed in Kenting National Park, Taiwan. The specific name alsinoides means ‘resembling Alsine’, a former genus of sandworts in the pink family (Caryophyllaceae), today split into Minuartia and other genera. (Photo copyright © by Kaj Halberg)
‘Long-term’ parked car in the city of Taichung, Taiwan, overgrown by various plants, e.g. obscure morning-glory (Ipomoea obscura), a climber of the pea family with chocolate-brown flowers, and downy bur-marigold (Bidens pilosa), an invasive species, which is abundant in Taiwan (the plant with white ray-florets). – Read more about downy bur-marigold on this website, see Nature: Invasive species. (Photo copyright © by Kaj Halberg)
The morning-glory, or bindweed, family (Convolvulaceae) is a large family of c. 55 genera, comprising more than 1,650 species, most of which are herbaceous vines, but also some erect herbs, shrubs, and trees. The flowers of almost all species are funnel-shaped, with five fused petals, and many are quite showy. The leaves are simple and alternate, often heart-shaped, and without stipules (the small growths on each side of the base of the leaf-stalk).
The stems of most of these plants are winding, hence the scientific name of the family, from the Latin convolvere, ‘to wind’. In his delightful book All about Weeds, American botanist Edwin Spencer (1881-1964) writes, “The vines wind themselves around the growing cornstalks, soy beans, cotton plants, and even around weeds that should be able to cope with such weak little plants as the morning glories seem to be. But they are not weak. Like snakes, those slender vines crawl up over the plants they select for their trellises, and soon the big morning glory leaves are shading the leaves of the trellising plants, and very soon after that those glorious flowers will be smiling on all the world like a big woman obstructing the view of a small boy at the movies.”
The type genus of this family is Convolvulus, the bindweeds, comprising c. 190 species, distributed over most of the world, with the greatest diversity in the Middle East. Most species in this genus are twining herbs, although quite a few are woody shrubs.
The type species of the type genus, the field bindweed (Convolvulus arvensis), named in 1753 by Swedish naturalist Carl von Linné (1707-1778), also called Carolus Linnaeus, is native to Europe and Temperate Asia, but has been accidentally introduced to many other parts of the world, where it has become invasive in many places. (See elsewhere on this website, Nature: Invasive species). This picture shows a large growth at a road side in Zealand, Denmark. (Photo copyright © by Kaj Halberg)
The flowers of field bindweed are usually white, often with pink markings here and there, as in these pictures from Bornholm, Denmark (top), and Skåne, Sweden. (Photos copyright © by Kaj Halberg)
Dwarf bindweed (Convolvulus tricolor) is native to the western Mediterranean, found in Spain, Portugal, and north-western Africa. In this picture, it grows together with love-in-a-mist (Nigella damascena), near San Martin el Tesarillo, Andalusia. (Photo copyright © by Kaj Halberg)
Convolvulus hystrix is a low, tangled shrub with numerous branches, ending in sharp spines. It is distributed from Egypt south to Somalia, and in the Arabian Peninsula, south to Yemen and Oman. This picture is from Ras Muhammad on the Sinai Peninsula. (Photo copyright © by Kaj Halberg)
Chilean bindweed (Convolvulus chilensis) is a shrub, which is endemic to northern and central Chile, growing to an altitude of c. 1,800 metres. This one was observed in Valle del Encanto, near the town of Ovalle. (Photo copyright © by Kaj Halberg)
Splendid bindweed (Convolvulus dorycnium), near Gournes, Crete. This shrub, which has stiff branches, grows to 1 m high. It is distributed in the southern part of Greece, Cyprus, Turkey, the Middle East, east to Iran, and in Egypt, Libya, and Tunisia. (Photo copyright © by Kaj Halberg)
False bindweeds, genus Calystegia, are herbaceous vines, growing to 5 metres long, or more, twining around other plants. Formerly, the c. 25 species of this genus were included in the genus Convolvulus, which they closely resemble, only differing in minute botanical characters. They are distributed in temperate and subtropical areas around the world, with almost half of the species being endemic to California.
The hedge bindweed (Calystegia sepium) has a very wide distribution, found in the northern and southern temperate zones. Due to its vigorous growth, it is regarded as a pest in many places. The common name, as well as the specific name sepium (‘in hedges’ in Latin), refers to the fact that this species often grows in hedges. Common names include old man’s nightcap and white witch’s hat, referring to the flower shape, while belle of the ball, bride’s gown, and wedlock refer to the white gown-like flowers, the latter name also to the binding nature of this species. Formerly, children in Britain would ‘pop’ the petals from the sepals while chanting, “Granny, granny – pop out of bed.”
Hedge bindweed (Calystegia sepium), Funen, Denmark. The plant in the foreground is rough chervil (Chaerophyllum temulum). (Photo copyright © by Kaj Halberg)
Hedge bindweed, entwining the stem of a giant goldenrod (Solidago gigantea), Zealand, Denmark. (Photo copyright © by Kaj Halberg)
This hedge bindweed, photographed shortly after a rain shower, is climbing up a fence near Hallein, Austria. (Photo copyright © by Kaj Halberg)
The American hedge bindweed (C. sepium ssp. americana) has a white and pink corolla, much like the cultivated hairy bindweed (C. pulchra). This subspecies is distributed across southern Canada and the eastern half of the United States, replaced by other subspecies further west. This picture is from Parker River National Wildlife Refuge, Massachusetts. (Photo copyright © by Kaj Halberg)
Ipomoea is a huge genus, comprising more than 500 species, most of which are twining plants with large, beautiful flowers. The generic name, from the Greek, ip = worm, and hómoia = resembling, was given by Swedish naturalist Carl von Linné (1707-1778), also called Carolus Linnaeus, in allusion to the worm-like movements of the stem, twining around other plants, abandoned buildings, fences, etc.
As its name implies, flowers of the purple morning-glory (Ipomoea purpurea) are purple. However, they can be white or various shades of blue, and cultivated varieties come in other colours, e.g. red or multi-coloured. This plant is native to Mexico and Central America, but has become naturalized in many other parts of the world, such as these, growing in the Marsyangdi Valley, central Nepal. In the upper picture, a species of buckwheat, Fagopyrum dibotrys, and downy bur-marigold (Bidens pilosa) are also seen. (Photos copyright © by Kaj Halberg)
Flower of purple morning-glory, photographed shortly after a rain shower, Flores, Lago Peten Itza, Guatemala. (Photo copyright © by Kaj Halberg)
The railroad creeper (Ipomoea cairica), also called coast morning-glory or mile-a-minute vine, is believed to be a native of Tropical Africa, but today it has a very wide distribution in tropical and subtropical areas around the world. This species is capable of very rapid growth, sometimes completely entwining trees and bushes, but it is also able to creep along the ground. It is regarded as an invasive species in many areas, including Australia, China, and Taiwan. These pictures are from Taiwan, where it is extremely common. (Photos copyright © by Kaj Halberg)
This species of morning-glory, Ipomoea imperati, grows on sandy beaches in warmer areas around the globe, here in Tortuguero National Park, Limón, Costa Rica. (Photo copyright © by Kaj Halberg)
Flowers of the blue morning-glory (Ipomoea nil) are various shades of blue, with a white funnel. This species, which is also called ivy-leaved, or Japanese morning-glory, can be told from similar species by the base of the calyx being hairy (clearly seen in the close-up photos). It is thought to be a native of Mexico or Central America, but has been widely introduced elsewhere in warmer countries as an ornamental, or accidentally. The plant in the upper two pictures is entwining a species of mugwort (Artemisia) in the Marsyangdi Valley, central Nepal, while the plant in the lower two, a pale blue form, is climbing up a fence in the city of Taichung, Taiwan. (Photos copyright © by Kaj Halberg)
Tievine (Ipomoea cordatotriloba) is a proliferate plant, native to south-eastern United States, Mexico, Central America, and parts of South America. In these pictures, it has enveloped a bush at Monterrico, Guatemala. (Photos copyright © by Kaj Halberg)
The beach morning-glory (Ipomoea pes-caprae) is very common on sandy beaches in all tropical and some subtropical areas, easily spreading by its seeds, which are able to float for a long time, unaffected by salt water. The specific name, pes-caprae, is from the Latin pes (‘foot’) and capra (‘goat’), referring to the shape of its leaves, which, to Swedish naturalist Carl von Linné (1707-1778), also called Carolus Linnaeus, resembled the footprint of a goat. – These pictures are from Puri, Odisha (Orissa), India (top), Siao Liouchou Island, Taiwan (two centre pictures), and Tortuguero National Park, Limón, Costa Rica. (Photos copyright © by Kaj Halberg)
The obscure morning-glory (Ipomoea obscura), also called small white morning-glory, is native to the southern half of Africa, tropical Asia, northern Australia, and some Pacific Islands, e.g. Fiji, and has been introduced elsewhere as an ornamental, or accidentally. It can be identified by its small, heart-shaped leaves and the 2-3 cm wide, white flowers with a brownish base. These pictures are from Taiwan, where this species is quite common. In the upper picture, a plant creeps along an unused asphalt road, while the one in the lower picture is climbing along barbwire. (Photos copyright © by Kaj Halberg)
Kenyan morning-glory (Ipomoea jaegeri) is an erect shrub, growing to 75 centimetres tall, often forming dense clumps. It is native to East Africa, where it grows on savannas. These pictures are from the Olduvai Gorge, Serengeti National Park, Tanzania. (Photos copyright © by Kaj Halberg)
The cardinal creeper (Ipomoea quamoclit) is easily identified by its bright red flowers and almost pinnate leaves. This species, which is also called star glory, cypress vine, or hummingbird vine, is a native of Mexico, Central America, and parts of South America. It is widely cultivated elsewhere in warm countries, often escaping and becoming naturalized. The specific name quamoclit is from a Nahuatl word, qua’mochitl, of unknown meaning. – This picture is from Pokhara, Nepal. (Photo copyright © by Kaj Halberg)
The flowers of the scarlet morning-glory (Ipomoea hederifolia), also called scarlet creeper, resemble those of the cardinal creeper, but its leaves are heart-shaped. It is likewise a native of Mexico, Central America, and parts of South America, and has also escaped cultivation in many countries. This picture is from Dunhinda Falls, near Badulla, Sri Lanka. (Photo copyright © by Kaj Halberg)
The place of origin of the water morning-glory (Ipomoea aquatica) is unknown. This plant is cultivated in many tropical and subtropical areas for its tender shoots and leaves, known by names such as water spinach, river spinach, Chinese spinach, Chinese watercress, and swamp cabbage. It has escaped cultivation in some areas, such as these, photographed in Keoladeo National Park, Rajasthan, India. (Photos copyright © by Kaj Halberg)
The blue dawn-flower, or Indian morning-glory (Ipomoea indica), is extremely variable, its leaves being heart-shaped or tri-lobed, and its flower colour varying from purple to blue to pink. It is sometimes called blue morning-glory, which is confusing, as this name is usually applied to Ipomoea nil (see above). The place of origin of blue dawn-flower is unknown. Today, its distribution is pan-tropical, and it is also found in some subtropical areas. It is regarded as an unwanted invasive plant in e.g. Australia, New Zealand, South Africa, California, and Portugal. These pictures show a purple form from Bali, Indonesia (top), a blue form from Pokhara, Nepal (second from above), a pale blue form from Yeliou Geopark, Taiwan (second from below), and a pink form from western Taiwan, together with downy bur-marigold (Bidens pilosa). (Photos copyright © by Kaj Halberg)
The pink morning-glory (Ipomoea carnea), a native of Mexico, Central America, and parts of South America, is an erect shrubby herb, growing to 3 metres tall. It is widely cultivated as an ornamental and has become naturalized in many areas, often regarded as an invasive. It is also grown in hedges and as green manure, and paper can be made from the stem. The leaves are sometimes eaten as a vegetable, although they are slightly purgative. This species is also utilized in traditional medicine as a sedative, and its latex is used for skin problems. The seeds are toxic to cattle. (Source: proseanet.org). – This growth was observed at Hampi, Karnataka, India. (Photo copyright © by Kaj Halberg)
Clustered morning-glory (Ipomoea staphylina) has rather small flowers, up to 3 centimetres across. Its common name, as well as the specific name staphylina, from the Greek staphyle (‘a bunch’), refer to the dense arrangement of the flowers. This species is native to the Indian Subcontinent, eastwards to China. In India, its stems are sometimes used as a rope to tie around collected firewood. – This plant was photographed near Mysore, Karnataka, India. (Photo copyright © by Kaj Halberg)
The sweet potato plant (Ipomoea batatas) is a most important crop in many tropical and subtropical countries around the world. Its large, sweet-tasting tubers resemble true potatoes (Solanum tuberosum), but the two species are only distantly related, as the true potato belongs to the nightshade family (Solanaceae). Young sweet potato leaves and shoots are eaten as a vegetable in many places. – These pictures show a flowering plant, growing in a field near Taichung, Taiwan, together with downy bur-marigold (Bidens pilosa) (top), and a woman, selling sweet potatoes and bananas at a market near Ngaunderé, Cameroun. (Photos copyright © by Kaj Halberg)
The genus Porana, comprising c. 20 species, is mainly found in tropical and subtropical Asia, with a few species in the Pacific, the Americas, and Africa. These plants resemble Ipomoea, but their sepals become much enlarged and papery when in fruit.
Porana grandiflora, sometimes called Tibetan moth vine, is found in the Himalaya, from Nepal east to Bhutan and extreme south-eastern Tibet, growing between 1,900 and 2,500 metres altitude. This plant was encountered in Helambu, Nepal. (Photos copyright © by Kaj Halberg)
Argyreia is a genus of woody shrubs or climbers, often with very showy flowers. It contains about 90 species, found in Tropical Asia, with one species reaching northern Australia.
Argyreia populifolia, a climber with wonderful whitish or pink flowers with a maroon throat, is distributed in India and Sri Lanka. This picture is from Anshi National Park, Karnataka. (Photo copyright © by Kaj Halberg)
Woodroses, genus Merremia, comprising c. 80 species, are distributed in tropical areas of Africa, Asia, Australia, and the Americas, with the largest concentration in Asia.
The ivy woodrose (Merremia hederacea), with bright yellow flowers, is widely distributed, found in Africa, the Indian Subcontinent, southern China, Taiwan, Southeast Asia, Malaysia, Indonesia, New Guinea, the Philippines, northern Australia, and some Pacific Islands. It is used medicinally for treating tonsillitis. – These pictures are from Taiwan, where this species is quite common. (Photos copyright © by Kaj Halberg)
The 8 species of the genus Dinetus were formerly included in Porana (see above). It is a purely Asian genus, distributed from Pakistan east across India and Nepal to China, and thence south through Southeast Asia to Indonesia and the Philippines.
The snow creeper (Dinetus racemosus) has about the same distribution as the genus. Its clusters of small white flowers are gorgeous, “resembling dazzling patches of snow in the jungle” (O. Polunin & A. Stainton (1984). Flowers of the Himalaya. Oxford University Press). These pictures are from Pokhara, Nepal, the upper one showing a snow creeper, climbing up a stem of an aibika (Abelmoschus manihot). (Photos copyright © by Kaj Halberg)
Dodders (Cuscuta) differ from other members of the morning-glory family in being parasites, which twine around other plants, often completely enveloping them. A dodder seed starts its life like most other seeds by sending roots into the soil, from which grow yellow, orange, or red stems, whose leaves are reduced to scales. When a stem gets into contact with a suitable plant, it wraps itself around it, inserting sucking organs, called haustoria, into the plant, through which the dodder obtains water and nutrients. Its root in the ground then dies.
This genus, comprising between 100 and 170 species, is distributed almost worldwide, with the greatest concentration in the tropics and subtropics. Temperate areas have much fewer species, e.g. northern Europe, where only four species are native. In hot climates, dodders are perennials, growing more or less continuously, while in colder areas they are annuals.
Their strange appearance taken into consideration, it is hardly surprising that dodders have many folk names, including strangleweed, scaldweed, beggarweed, lady’s laces, wizard’s net, devil’s guts, devil’s hair, devil’s ringlet, goldthread, hailweed, hairweed, hellbine, pull-down, angel’s hair, and witch’s hair.
The generic name is derived from the Arabic name for dodders, kusuta, or kuskut, which, in the form Cuscuta, was applied to them by Rufinus, an Italian monk and botanist, who was the author of De virtutibus herbarum, a work, which was completed c. 1287, listing nearly a thousand medicinal materials, mostly plants.
A species of dodder, probably California dodder (Cuscuta californica), also called chaparral dodder, has enveloped a bladderpod bush (Peritoma arborea), near Amboy, California. This species is common in chaparral, grasslands, pine forests, and other drier plant communities in western North America. (Photo copyright © by Kaj Halberg)
Greater dodder (Cuscuta europaea), a native of Temperate Eurasia, is partial to common nettle (Urtica dioica), although it can grow on plants of many other families. In these pictures, from the Lauterbrunnen Valley, Berner Oberland, Switzerland, and the island of Møn, Denmark, its host is common nettle. (Photos copyright © by Kaj Halberg)
This unidentified species of dodder has completely enveloped a bush in Monumento Natural El Morado, Chile. (Photo copyright © by Kaj Halberg)
Lesser dodder (Cuscuta epithymum), growing on a species of knapweed (Centaurea), Valle Hecho, Pyrenees, Spain. Its most common host species are heather (Calluna vulgaris), gorse (Ulex europaeus), and clover (Trifolium). It is native to Europe, but has been accidentally introduced to many other parts of the world. (Photo copyright © by Kaj Halberg)
Southern dodder (Cuscuta australis) has a very wide distribution, found from Africa, across the Middle East to India and the Far East, and thence southwards through Southeast Asia and Indonesia to New Guinea and Australia. These pictures are from Taiwan, where southern dodder is very common. (Photos copyright © by Kaj Halberg)
Giant Asian dodder (Cuscuta reflexa) is found from Afghanistan across the Indian Subcontinent and southern Tibet to south-western China, and thence south through Southeast Asia to Indonesia. This proliferate species is regarded as a serious pest in some areas, e.g. in the Valley of Flowers National Park, Uttarakhand, India. – In these pictures, it is enveloping a bush in Keoladeo National Park, Rajasthan, India (top), and a Lindera bush at Tharke Ghyang, Helambu, Nepal (centre). The bottom picture shows its small, bell-shaped flowers, photographed in the Marsyangdi Valley, central Nepal. (Photos copyright © by Kaj Halberg)
Fruits of most genera of the bindweed family are capsules, but a few species have berries or nuts. This picture shows capsules of a blue morning glory (Ipomoea nil), climbing on discarded pallets in the city of Taichung, Taiwan. (Photo copyright © by Kaj Halberg)
(Uploaded March 2018)