In praise of the colour blue



In the wonderful Monterey Aquarium in California, huge aquariums, containing various jellyfish, are brightly illuminated, on a blue background. The pictures below show purple-striped jellyfish (Chrysaora colorata) (top) and a species of moon jellyfish (Aurelia).



Californien 2011a
Californien 2011a
(Photos copyright © by Kaj Halberg)






The blue-shorts roller-skating club is out training, Taichung, Taiwan. (Photos copyright © by Kaj Halberg)






The Sri Lanka blue magpie (Urocissa ornata), formerly known as Ceylon magpie, is a gorgeous bird of the crow family (Corvidae), which is endemic to Sri Lanka. It is partial to tall, undisturbed, primary forest in the south-western wet zone of the island, from the lowlands up to an altitude of c. 2,100 m. Occasionally, this species will visit secondary forest or other disturbed areas, but it is continuously declining due to loss of suitable habitat. Its food mainly consists of frogs, lizards, insects and other invertebrates, and to some degree fruit.

Other members of the crow family are presented on the page Nature: Urban nature.



This Sri Lanka blue magpie in Sinharaja Forest Reserve is eating the red outer layer of a palm fruit. (Photo copyright © by Kaj Halberg)






Since 1975, the major part of larger elms (Ulmus) in Europe and North America have been killed by Dutch Elm disease, caused by the sac fungus Ophiostoma novo-ulmi (formerly Ceratocystis novo-ulmi), which is spread by elm bark beetles of the genera Scolytus and Hylurgopinus. It is generally believed that the disease originated in Asia, but was accidentally introduced to Europe and North America, where most native elm species had no resistance against the disease.

Dutch Elm disease is described in detail on the page Nature Reserve Vorsø: Dutch Elm disease on Vorsø.



On a silent summer night, these common elms (Ulmus glabra), which have been killed by Dutch elm disease, stretch their dead branches into the sky, Nature Reserve Vorsø, Horsens Fjord, Denmark, (Photo copyright © by Kaj Halberg)






The bellflower genus (Campanula) includes more than 500 species, found in temperate and subtropical areas of the Northern Hemisphere, with the highest diversity around the Mediterranean and in the Middle East. The generic name, as well as the name of the entire family, Campanulaceae, is due to the bell-shaped flowers of this genus, from the Latin campanula (’little bell’). Four species are presented below, whereas several others are described on the page Plants – Mountain plants: Flora of the Alps.


The widespread harebell (Campanula rotundifolia) is also known by a number of other names, including bluebell, lady’s thimble, witch’s bells, and witch’s thimbles. This species has a circumpolar distribution, growing between latitudes 40°N to about 78°N. It is very common in most parts of Europe, where it may be found from the Mediterranean northwards to the Arctic.



Sverige 2015
In this picture, harebell grows among red fescue (Festuca rubra) in the Hagestad Nature Reserve, Skåne, Sweden. (Photo copyright © by Kaj Halberg)




Peach-leaved bellflower (Campanula persicifolia) is native to the major part of Europe, excluding the British Isles, eastwards to western Siberia, southwards to North Africa, Turkey, the Caucasus, and Kazakhstan. It has also been introduced to the British Isles, Canada, and the United States, where it sometimes becomes naturalized.

In the northern part of its natural range, this species grows down to sea level, whereas in the southern part it is restricted to mountains. It is found in a wide variety of habitats, including grasslands, broad-leaved forest, and along streams. The specific and popular names were given in allusion to its leaves, which to some degree resemble those of peach (Prunus persica).



Peach-leaved bellflower, growing on a coastal bluff, northern Zealand, Denmark. (Photo copyright © by Kaj Halberg)




Campanula tomentosa, also called C. ephesia, is endemic to western Turkey, mainly growing on the Dilek Peninsula, which juts out into the Aegean Sea. It may also be found among the ruins of the ancient Greek city of Ephesus. The specific name is Latin, meaning ‘covered in rough hairs’, alluding to the dense hair cover on this plant. The alternative name ephesia means ‘from Ephesus’.



Campanula tomentosa, encountered among the ruins of Ephesus, western Turkey. (Photo copyright © by Kaj Halberg)




The gorgeous great bellflower (Campanula latiloba) is another Turkish endemic, which is restricted to a belt along the Black Sea coast.



Campanula latiloba, Kapisuyu, near Cide, Black Sea. (Photos copyright © by Kaj Halberg)




Sheep’s-bit (Jasione montana), which also belongs to the bellflower family, is distributed in Temperate Europe and western Asia. It prefers to grow on rather poor soil, including dunes and heathland.



Bornholm 2008a
On the island of Bornholm, Denmark, sheep’s-bit often grows among coastal rocks, in this case together with sweet vernal grass (Anthoxanthum odoratum). (Photo copyright © by Kaj Halberg)






The nilgai (Boselaphus tragocamelus) is a large, stout antelope, distributed in the major part of India, and also a small population in southern Nepal.

The name nilgai is Hindi for ‘blue cow’, referring to the slate-coloured, slightly bluish coat of the male, and to its similarity to the sacred cow. For the latter reason, the nilgai is protected by devout Hindus and has thus escaped the fate of many other animals in India, which are on the brink of extinction, such as tiger (Panthera tigris), lion (Panthera leo), and blackbuck (Antilope cervicapra). The coat of females and young males is a pale sandy brown. Both sexes have a white throat patch.

The scientific name of this antelope is quite peculiar. It is derived from four Greek words, bous (‘cow’), elaphos (‘deer’), tragos (‘goat’), and kamelos (‘camel’). The name was applied by Prussian naturalist Peter Simon Pallas (1741-1811), to whom this antelope apparently resembled a mixture of these four animals.



The name nilgai is Hindi for ‘blue cow’, referring to the slate-coloured, slightly bluish coat of the male, and to its similarity to the sacred cow. – Sariska National Park, Rajasthan, north-western India. (Photo copyright © by Kaj Halberg)



Asien 1977-78
Nilgai males, drinking from a waterhole in Sariska National Park. (Photo copyright © by Kaj Halberg)






The fate of many kites! Despite being designed as Superman, this kite ended in a tree. – Taichung Metropolitan Park, Taiwan. (Photo copyright © by Kaj Halberg)






Common viper’s bugloss (Echium vulgare) is native to most of Europe and northern Temperate Asia, and it has also become naturalized in parts of North America. The generic name is from the Greek echis, meaning ‘viper’, referring to the shape of the flower, with the long, red stamens sticking out like a viper’s tongue. The name bugloss is from the Greek, meaning ‘ox tongue’, referring to the rough surface of the leaves. In Swedish, the name of this species is blåeld, meaning ‘blue fire’, alluding to the wonderful blue colour of the flowers, which, when many plants grow together, does resemble ‘blue fire’.

Formerly, it was believed that this species could be used as a cure for snake bite. British herbalist Nicholas Culpeper (1616-1654) says about this: “It is a most gallant herb of the sun; it is a pity it is no more in use than it is. It is an especial remedy against the biting of the viper, and all other venomous beasts, or serpents; as also against poison, or poisonous herbs. Dioscorides and others say that whosoever shall take of the herb or root before they be bitten, they shall not be hurt by the poison of any serpent.” – Pedanius Dioscorides (died 90 A.D.), was a Greek physician, pharmacologist, and botanist, author of De Materia Medica (five volumes dealing with herbal medicine).



Norden 1992-98
Common viper’s bugloss, growing on a gravelly beach on the Swedish island of Gotland. (Photo copyright © by Kaj Halberg)



Bornholm 2008a
Common viper’s bugloss, photographed on the Danish island of Bornholm. (Photo copyright © by Kaj Halberg)






Water is sprouting out through numerous tiny holes in this sculpture, erected in front of Silkeborg Art Museum, Jutland, Denmark. (Photo copyright © by Kaj Halberg)






Tyrkiet 2006
This elderly woman, clad in blue, has displayed vegetables for sale at the road side, Amasra, northern Turkey. (Photo copyright © by Kaj Halberg)






Dayflowers (Commelina) is a genus of anywhere between 100 and 170 species, found in tropical and subtropical regions around the world. These plants are called dayflowers due to their flowers, which usually only live for one day. When Swedish naturalist Carolus Linnaeus (1707-1778), also called Carl von Linné, named this genus, he let the two showy blue petals of Commelina communis represent two Dutch botanists, Jan Commelijn and his nephew Caspar, whom he wished to honour.

Dayflowers have 3 petals, the upper 2 being bright blue or indigo, whereas the much smaller lower petal is white. Each flower has 6 stamens, 3 upper ones with yellow anthers, which are sterile, and 3 lower ones with white or purple anthers, which are fertile.


The Asiatic dayflower (Commelina communis) is native to large parts of eastern Asia, from Ussuriland, south-eastern Russia, southwards through China, Korea, Japan, and Taiwan to the northern part of Southeast Asia and extreme eastern India. It has also been introduced to western Russia, south-eastern Europe, and eastern North America, where it has become invasive in several places. In Chinese traditional medicine, the dried plant is utilized to treat a number of ailments, including sore throat, colds, oedema, bruises, and limited urination. A near relative, Commelina benghalensis, is eaten as a vegetable in Southeast Asia and Africa.



Asiatic dayflower, growing along a street in Taichung, Taiwan, adorned with pebbles, which have been painted blue. (Photo copyright © by Kaj Halberg)



This Asiatic dayflower has sprouted next to a house wall in Taichung. (Photo copyright © by Kaj Halberg)






Beehives are a very common sight on the Greek island of Crete. These have been painted blue and white – the colours of the Greek national flag. (Photo copyright © by Kaj Halberg)






Blue anemones (Hepatica), also called hepatica, liverleaf, or liverwort, were named for their mostly three-lobed leaves, hepatica being derived from the Greek hepar (‘liver’). As the outline of the leaf resembles the human liver, followers of the Doctrine of Signatures claimed that they could be used for treatment of liver disorders. This is not the case, but the plant has been used to treat wounds, as an astringent, and as a diuretic.

This genus of the buttercup family (Ranunculaceae), which is native to Eurasia and eastern North America, has caused much confusion among taxonomists as to the number of species, which varies from seven to thirteen, depending on authority. Others treat these plants as members of the genus Anemone, which, together with the genus Pulsatilla, is dealt with in detail on the page Plants: Anemones and pasque flowers.

The genus includes the following species, subspecies, and/or varieties:


Hepatica nobilis var. nobilis (European hepatica, or blue anemone), found from Scandinavia and the Baltic southwards to Italy and the Balkans.
H. pyrenaica = H. nobilis var. pyrenaica (Pyrenean hepatica), the Pyrenees and northern Spain.
H. transsilvanica (Romanian hepatica), restricted to mountains in Romania.
H. falconeri, montane forests of Central Asia.
H. asiatica = H. nobilis var. asiatica, central and eastern China, Korea, and south-eastern Siberia.
H. henryi, central and western China.
H. yamatutai, restricted to Mount Emei Shan, Sichuan Province, China.
H. insularis, southern Korea.
H. maxima, endemic to Ulleung-do Island, Korea.
H. japonica = H. nobilis var. japonica, Japan.
H. pubescens = H. nobilis var. pubescens, central Honshu, Japan.
H. americana = H. nobilis var. obtusa (round-lobed hepatica), eastern North America.
H. acutiloba = H. nobilis var. acuta (sharp-lobed hepatica), eastern North America.



Large growth of European hepatica (Hepatica nobilis var. nobilis), Knisa Mosse, Öland, Sweden. (Photo copyright © by Kaj Halberg)



European hepatica (Hepatica nobilis var. nobilis), eastern Jutland, Denmark. (Photo copyright © by Kaj Halberg)



Round-lobed hepatica (Hepatica americana), Clement Farm Conservation Area, Massachusetts, United States. (Photo copyright © by Kaj Halberg)






Construction of the Topkapı Sarayı (‘Topkapi Palace’) in Istanbul, Turkey, began in 1459, ordered by Sultan Mehmed II (1432-1481), commonly known as Mehmed the Conqueror. Originally, this palace was called Yeni Saray (‘New Palace’) to distinguish it from an older palace in the city. The name Topkapı (‘Cannon Gate’) was applied to it in the 19th century. This palace served as seat for Ottoman Sultans for more than 500 years.



Tyrkiet 2018
Tyrkiet 2018
Tyrkiet 2018
Colourful Chinese tiles, Topkapı Sarayi, Istanbul. (Photos copyright © by Kaj Halberg)






In the past, the white-tailed blue robin (Myiomela leucura) was regarded as belonging to the thrushes, but recent DNA studies indicate that it is in fact a flycatcher of the family Muscicapidae. It is distributed from the Himalaya eastwards across Southeast Asia, with an isolated population, subspecies montium, in the lower mountains of Taiwan.

This species lives in dense forest and bamboo growths, feeding on the ground. Male and female have a very different plumage, the male being dark blue with pale-blue forehead and wing coverts, and a black tail with a large white spot at the base of each side, while the female is brown with a whitish throat, its tail being similar to that of the male.



This male white-tailed blue robin was photographed in a dense thicket in Dasyueshan National Forest, central Taiwan. (Photo copyright © by Kaj Halberg)






Artwork, exhibited near the Hoan Kiem Lake, Hanoi, Vietnam. (Photos copyright © by Kaj Halberg)






Eight species of rollers, of the genus Coracias, are colourful birds, displaying bright blue or turquoise on various parts of their body. They are often perched on a prominent branch, or a fence post, scanning the surrounding landscape for prey, which includes various invertebrates, and small vertebrates such as lizards, snakes, frogs, rodents, and young birds. Most of the species live in sub-Saharan Africa, with one species in Europe and western Asia, one widespread Asian species, and one species in Sulawesi.



The Eurasian roller (Coracias garrulus) breeds in eastern Europe and south-western Asia, with a disjunctive population in extreme southern France, Spain, Portugal, and north-western Africa. The winter months are spent in Africa, the Iberian and North African populations migrating to West Africa, from Sierra Leone eastwards to Cameroun, while eastern populations migrate to southern Africa. This species has declined rather drastically in most of its breeding area. Threats include hunting during migration, especially in Oman, where thousands are killed for food. In many places, trees have been removed, giving way to modern agricultural practices, robbing the roller of potential nesting sites and perches for hunting, while pesticides have reduced its food sources.



Tanzania 1993
Eurasian roller, photographed in Tarangire National Park, Tanzania, in early April, when the north-going migration of this species takes place. (Photo copyright © by Kaj Halberg)




The Indian roller (Coracias benghalensis) has a wide distribution, from Iraq and the Arab Emirates, eastwards along coastal Iran and the entire Indian Subcontinent, including Sri Lanka and the Maldive Islands, to Southeast Asia. It is very common in India, where several states have chosen it as their state bird.



Sydasien 1978-79
A gorgeous Indian roller takes off from a thicket in Yala National Park, Sri Lanka. (Photo copyright © by Kaj Halberg)




The lilac-breasted roller (Coracias caudatus) is rather common in open woodland and savanna in eastern and southern Africa, from Ethiopia southwards to South Africa, and thence westwards to Namibia. It is easily identified by its lilac breast.



Sydafrika 2003
In this picture from Kruger National Park, South Africa, a gust of wind ruffles the plumage of a lilac-breasted roller. (Photo copyright © by Kaj Halberg)



Kenya 1988-89
Male lilac-breasted roller, bringing food to his mate, who greets him by calling. (Photo copyright © by Kaj Halberg)




The Abyssinian roller (Coracias abyssinicus) breeds across the African Sahel zone, southwards to Cameroun, Central African Republic, northern Zaire, northern Uganda, and northern Kenya, and is also found along the southern Red Sea coast on the Arabian Peninsula, and along the Nile River, almost to the Egyptian border. Its outer tail feathers are very long and thin.



Afrika 1980-81
Abyssinian roller, Waza National Park, Cameroun. (Photo copyright © by Kaj Halberg)




The purple, or rufous-crowned, roller (Coracias naevius) is less colourful than the other rollers of this genus. It is very widespread in sub-Saharan Africa, excepting the West African rainforest belt and extreme southern Africa. Its preferred habitat is dry savanna, and its breeding season varies from place to place, possibly linked to recent rains.



Kenya 1988-89
Purple roller, Lake Bogoria, Kenya. (Photo copyright © by Kaj Halberg)






In a suburban area in Taichung, a retired soldier has adorned an entire neighbourhood – walls, streets, doors – with colourful paintings. For this reason, the area has been dubbed Tsai Hung Tsun (‘Rainbow Village’). The picture below shows an example of his art, whereas others are shown on the page Culture: Folk art in Taiwan.



Taiwan 2013
(Photo copyright © by Kaj Halberg)






The black-naped monarch (Hypothymis azurea), of the monarch-flycatcher family (Monarchidae), has a very wide distribution, found in the Indian Subcontinent, Southeast Asia, Malaysia, Indonesia, the Philippines, Southern China, and Taiwan. No less than 23 subspecies have been described. The male is bright blue with a distinctive black patch on the crown and a narrow black stripe across the throat, while the female is dull-blue with brownish wings, lacking the black markings of the male.



In Taiwan, the black-naped monarch, subspecies oberholseri, is quite common in forests in lower parts of the country. This male was feeding in a dense growth of trees in a city park in Taichung. (Photos copyright © by Kaj Halberg)






The narrow-leaved, or cowslip lungwort (Pulmonaria angustifolia), is similar to common lungwort (P. officinalis), but has narrower leaves and sky-blue flowers. It is native to central and eastern Europe, but is nowhere common.



Narrow-leaved lungwort, photographed in Denmark, where it is extremely rare, growing on a single coastal bluff in northern Zealand. (Photo copyright © by Kaj Halberg)






Manhattan, New York City, by night, seen from Brooklyn Bridge. – To commemorate the Twin Towers of the World Trade Center, which were destroyed during a terrorist attack on September 11, 2001, two blue laser beams are cast into the air, six months later, on the original location of the towers.



USA 2002-10
(Photo copyright © by Kaj Halberg)






Lasianthus is a genus of about 180 species of tropical and subtropical plants in the bedstraw family (Rubiaceae), varying in size from small shrubs to small trees. They are primarily found in the understory of forests. The core area of the genus is Malaysia and Indonesia with c. 130 species, whereas about 30 species are found in warmer areas elsewhere in Asia, 15 to 20 species in tropical areas of Africa, one in Queensland, Australia, and two in the Neotropics. The fruit is a small drupe, usually blue.

This genus was described by Scottish botanist and physician William Jack (1795-1822), who worked as a surgeon in India, and later in Sumatra, where he died in 1822, presumably of malaria. The generic name is derived from the Greek lasios (‘shaggy’) and anthos (‘flower’), the name given in allusion to the rather shaggy appearance of the flowers of most members of the genus.


Lasianthus fordii is a small shrub, to 2 m tall, which grows in humid, shaded forests at altitudes between 200 and 1,000 m, from southern Japan and China southwards through Southeast Asia and the Philippines to Indonesia and New Guinea.



Fruits of Lasianthus fordii are a gorgeous shade of blue. – Sun-Moon Lake, Taiwan. (Photo copyright © by Kaj Halberg)





Another genus in the bedstraw family with bright blue or purple berries is Coccocypselum, which is native to Central and South America, and the West Indies.


Coccocypselum hirsutum is a creeping herb, distributed from Mexico southwards to Paraguay and southern Brazil. As its specific name implies, from the Latin hirtus (‘hairy’ or ‘rough’), this species is hairy, on stems, leaves, and fruits.



Bright blue fruits of Coccocypselum hirsutum, Parque Nacional Volcán Arenal, Cordillera de Tilarán, Costa Rica. (Photo copyright © by Kaj Halberg)






The blue tit (Cyanistes caeruleus), named for its blue crown, wings, and upper tail, is a widespread breeding bird in Europe, from northern Scandinavia southwards to Spain, Italy, Greece, and Turkey, and from the British Isles eastwards to western Iran. In Siberia and Central Asia, it is replaced by a near relative, the azure tit (C. cyanus), which is a very rare guest in Europe.

The blue tits of northern Africa and the Canary Islands, which were formerly included in C. caeruleus, are now regarded as a separate species, the African blue tit (Cyanistes teneriffae), divided into six or seven subspecies.



This blue tit is removing small bits of decayed wood from its nesting hole in an elder (Sambucus nigra), Nyord, Møn, Denmark. (Photos copyright © by Kaj Halberg)






Primroses, or cowslips, genus Primula, are distributed in temperate areas of the Northern Hemisphere and in Temperate South America. This genus probably originated in the Himalaya, where no less than c. 70 species grow. The name cowslip is interpreted in various ways. According to some authorities, it is a corruption of the Old English word cuslyppe, meaning ‘cow dung’. This probably refers to the favoured habitat of several primrose species, namely cattle grazing grounds. Others claim that the word is a corruption of cow’s leek, derived from the Anglo-Saxon word leac, meaning ‘plant’.

You may read more about primroses on the pages Plants: Primroses, and Plants: Plants in folklore and poetry.


With its broadly bell-shaped flowers, Primula wollastonii differs significantly from most other species of the genus. It is found in central and eastern Nepal, and southern Tibet, between 3,600 and 4,900 m altitude.



Everest 2010
Primula wollastonii, Gokyo Valley, Khumbu, eastern Nepal. (Photo copyright © by Kaj Halberg)






Chile 2011a
Gaily coloured houses, Valparaiso, Chile. (Photo copyright © by Kaj Halberg)






The male grandala (Grandala coelicolor) is a gorgeous bird, whose plumage is an almost iridescent hue of blue, whereas the female is greyish with faint white stripes on head, nape, and breast, and a brownish tinge to the wings. This species is distributed from Kashmir along the entire Himalayan chain, and thence northwards through eastern Tibet to western China, from northern Yunnan northwards to eastern Qinghai. It breeds at very high altitudes, between 4,000 and 5,500 m, moving to slightly lower elevations in winter.

Classification-wise, this species has been knocked about a great deal. Initially, it was regarded as belonging to the thrush family, but following genetic studies it was then transferred to the flycatcher family (Muscicapidae). However, recently it has been moved back to the thrush family!



Everest 2010
From a stone in a mountain stream in the Gokyo Valley, Khumbu, eastern Nepal, this male grandala would alight and flutter about butterfly-like to snap an insect, before returning to its vantage point. (Photo copyright © by Kaj Halberg)






The five-striped blue-tailed skink (Plestiodon elegans) is distributed in southern China, Vietnam, Taiwan, and the southernmost islands in Japan.



Taiwan 2017a
Immature five-striped blue-tailed skink, photographed on Bagua Shan, western Taiwan. Adults do not have a blue tail. (Photo copyright © by Kaj Halberg)






Swinhoe’s pheasant (Lophura swinhoii), also known as Taiwan blue pheasant, is endemic in the mountains of central Taiwan, where it is quite common. It is named after British biologist Robert Swinhoe (1836-1877) who, in 1860, became the first European consular representative to Taiwan. He discovered many new species, and four mammals and 15 birds are named after him.

To lure this gorgeous bird closer, many Taiwanese photographers strew maize or other food near roads or trails, often causing it to become remarkably tame.



Male Swinhoe’s pheasant, Dasyueshan National Forest. (Photo copyright © by Kaj Halberg)






Puya is a genus of large plants of the pineapple family (Bromeliaceae), restricted to the Andes Mountains and mountains of southern Central America.



Chile 2011a
Gorgeous blue flowers of Puya coerulea, encountered in Reserva Nacional Rio Clarillo, Chile. (Photo copyright © by Kaj Halberg)






Nepal 2013
Many houses in the town of Taplejung, eastern Nepal, are painted blue. (Photo copyright © by Kaj Halberg)






The gorgeous butterfly pea (Clitoria ternatea), also called Asian pigeon-wings or bluebell vine, is a native of the southern Arabian Peninsula and Tropical Asia, and has been widely introduced elsewhere as an ornamental, including Africa, Australia, and America. It was first named Lathyrus spectabilis by Swedish naturalist Pehr Forsskål (1732-1763), in Yemen, during the Royal Danish Expedition to Arabia 1761-1767. Later, it was renamed Clitoria ternatea by Forsskål’s mentor, the famous Swedish botanist Carolus Linnaeus (1707-1778), also known as Carl von Linné. Nobody can doubt what he was referring to!

This plant is widely utilized in traditional Ayurvedic medicine for various purposes, including as an anti-depressant, a tranquilizer, and a sedative. In traditional Chinese medicine, it has been used for female diseases due to its similarity to the female reproductive organ – a typical example of the Doctrine of Signatures, whose followers claim that the Great God made all plants, so that humans would recognize the usage of them.

In China, Taiwan, and Southeast Asia, the flowers are used as a natural food colouring.

The fascinating, albeit short, life of Pehr Forsskål is related on the page People: Pehr Forsskål – brilliant Swedish scientist.



Sydindien 2008
Butterfly pea, photographed near Kenting, southern Taiwan (top), and near Mysore, Karnataka, South India. (Photos copyright © by Kaj Halberg)






In former days, bluestarts, or bush-robins, were regarded as small thrushes, but recent DNA analyses have revealed that they are in fact ground-living flycatchers of the family Muscicapidae. The most widespread species is the common bluestart (Tarsiger cyanurus), found from eastern Europe across Siberia, southwards to Japan and the Himalaya.



Nepal 2002
This picture from Sagarmatha National Park, eastern Nepal, shows a male Himalayan bluestart (Tarsiger cyanurus ssp. rufilatus), by some authorities regarded as a separate species, T. rufilatus. (Photo copyright © by Kaj Halberg)






Iris is a genus of wonderful plants, comprising 250-300 species. They are named after Iris, the Greek goddess of the rainbow, presumably because of their colourful flowers. Other species of this attractive genus are presented on the pages Plants – Mountain plants: Himalayan flora, and In praise of the colour yellow.



USA 2012a
Some American species of Iris are called ‘flag’, including northern blue flag (Iris versicolor), here photographed in Pawtuckaway State Park, New Hampshire. (Photo copyright © by Kaj Halberg)






The Tuaregs, also known by various other names, including Kel Tamasheq, Imuhagh, Imazighen, or Itargiyen, are a large group of Berber peoples, living in the western half of the Sahara Desert, southwards to Niger, Mali, and Burkina Faso. The Tuaregs have often been called the Blue People, because they dye their clothes with indigo, the blue colour of which stains their skin.



I met this Tuareg south of Arlit, Niger. (Photo copyright © by Kaj Halberg)






Blue trumpet-vine (Thunbergia grandiflora), also known as Bengal clock-vine or sky-vine, is a huge climber of the acanthus family (Acanthaceae), growing to a length of 20 m or more. It is native to South and Southeast Asia and China, but has become widely naturalized elsewhere. In parts of Australia, it is regarded as a serious invasive.

In Spanish, this plant is called Emperatriz Eugenia, named for Doña María Eugenia Ignacia Augustina de Palafox y KirkPatrick (1826-1920), wife of French Emperor Napoleon III and known as Eugénie de Montijo in French.

The generic name was given in honour of Swedish botanist and physician Carl Peter Thunberg (1743-1828), a pupil of Carolus Linnaeus (1707-1778), also called Carl von Linné. Thunberg is mainly known for his botanical work in South Africa and Japan.

A near relative of blue trumpet-vine is black-eyed Susan (Thunbergia alata), which is described on the page In praise of the colour yellow.



Blue trumpet-vine, encountered on Peninsula de Osa, Costa Rica. (Photo copyright © by Kaj Halberg)






Neither of the two North American ‘blue’ herons, the great blue (Ardea herodias) and the little blue (Egretta caerulea), are really blue, but have a bluish tinge to their plumage. They are both widely distributed, the great blue from Alaska southwards to extreme north-western South America, while in North America, the little blue is restricted to the United States east of the Rockies, but is found further south than the great blue, southwards to Peru and Brazil.

Many more heron species are presented on the pages Animals: Birds in Taiwan, and Fishing.



Californien 2013b
Great blue heron, feeding on a grassy plain in Ronald W. Caspers Wilderness Park, Santa Ana Mountains, California. (Photo copyright © by Kaj Halberg)



USA 1998-99
Little blue heron, Everglades National Park, Florida. (Photo copyright © by Kaj Halberg)






Schizanthus hookerii is a beautiful plant of the nightshade family (Solanaceae), also called butterfly flower, fringe flower, and poor man’s orchid. The flowers of this genus, which is native to Chile and Argentina, are pollinated by bees, bumblebees, and wasps.



Chile 2011a
Schizanthus hookerii, Reserva Nacional Altos de Lircay, Chile. (Photo copyright © by Kaj Halberg)






Gossamer-winged butterflies (Lycaenidae) is a very large butterfly family with over 4,500 species worldwide, constituting more than 20% of all known butterfly species (excluding moths). Traditionally, the family is divided into a number of subfamilies, of which the blues (Polyommatinae), is the largest.



Fanø 2001-12
Male common blue (Polyommatus icarus), feeding in thrift flowers (Armeria maritima), Fanø, Denmark. A hovering fly is seen in the foreground. (Photo copyright © by Kaj Halberg)



Cambodia 2010
Common tit (Hypolycaena erylus), sucking sweat from my finger, Ta Prohm, Angkor Wat, Cambodia. (Photo copyright © by Kaj Halberg)






Cow-wheat (Melampyrum), comprising c. 40 species of parasitic plants in the broomrape family (Orobanchaceae), are distributed in arctic and temperate regions of the Northern Hemisphere, southwards to Spain, Turkey, and China, and the Carolinas in America.

The generic name is from the Greek melampyron, of melas (‘black’) and pyros (‘wheat’), referring to the black seeds, which somewhat resemble wheat grains. An ancient belief has it that the seeds, when mixed with wheat and ground into flour, tended to make the bread black. In the Middle Ages, it was also believed that the seeds were capable of being converted into wheat, supposedly because of the sudden appearance of these plants among wheat, planted on recently cleared land. Cows and sheep readily eat these plants, hence the name cow-wheat. (Source: M. Grieve, 1931. A Modern Herbal. Jonathan Cape, here taken from

In his Cruydeboeck (herb book), Flemish physician and botanist Rembert Dodoens (1517-1585) tells us that “the seeds of this herb taken in meate or drinke troubleth the braynes, causing headache and drunkennesse.”


Popular names of the wood cow-wheat (Melampyrum nemorosum) include natt-och-dag (‘night-and-day’ in Swedish) and Ivan-da-Marya (‘Ivan-and-Maria’ in Russian), both names referring to its striking inflorescences, with yellow flowers and bright purplish-blue bracts. This species is mainly a plant of eastern Europe, found from Denmark, Germany, and Italy, eastwards to north-western Russia.



Sverige 2016-18
Wood cow-wheat, growing along a hedge on the island of Öland, Sweden. (Photo copyright © by Kaj Halberg)






Iznik tiles are decorated ceramics, named after the Turkish city of Iznik, situated just east of the Marmara Sea, where these exquisite ceramics were produced, mainly between the late 1400s and the late 1600s. They were decorated with cobalt blue and other colours under a colourless, transparent lead glaze. (Source:

The man in the picture below is reading his newspaper, while waiting for customers in his shop, situated in the Kapalıçarşı (‘Covered Market’), or Büyük Çarşı (‘Grand Bazaar’), Istanbul. His tiles and other ceramics are clearly inspired by the famous Iznik tiles.



Tyrkiet 2018
(Photo copyright © by Kaj Halberg)



Tyrkiet 2018
Obviously, the paintings on these gas bottles in Istanbul are also inspired by the Iznik tiles. (Photo copyright © by Kaj Halberg)






Tanagers are a huge American family of passerines, Thraupidae, comprising at least 200 species, of which the majority are found in Mexico, Central America, and South America. Traditionally, about 240 species were included in this family, but, following genetic research, some species have been transferred to the finch family (Fringillidae) or to the cardinal family (Cardinalidae).


The blue-grey tanager (Thraupis episcopus) is common in open woodland, gardens, and cultivated areas, from Mexico through Central America southwards to Bolivia and northern Brazil. It is also found on the Caribbean islands Trinidad and Tobago, and has been introduced to Peru, around the capital Lima.



Costa Rica-2
This blue-grey tanager is feeding on a fallen fruit of great morinda (Morinda citrifolia), Tortuguero National Park, Costa Rica. (Photo copyright © by Kaj Halberg)




The gorgeous red-legged honeycreeper (Cyanerpes cyaneus) is another member of the tanager family, which is distributed from southern Mexico southwards to Peru, Bolivia, and central and eastern Brazil. It is also found on several Caribbean islands, including Trinidad and Tobago, and Cuba.



Costa Rica-2
Male red-legged honeycreeper, feeding in flowers of blue porterweed (Stachytarpheta frantzii), Cordillera de Tilarán, Costa Rica. (Photo copyright © by Kaj Halberg)






The theme on the local banner of the Swedish island Öland is identical to the official heraldic coat of arms of the island, dating back to c. 1560: a blue sheet of bunting, depicting a golden stag with red antlers, tongue, and hooves, and wearing a red collar – a symbol of Öland as a royal hunting area.



Sverige 2015
This Öland banner was fluttering in the wind outside a farm in the village of Gillsätra. (Photo copyright © by Kaj Halberg)






Blueberries comprise 21 bushes of the genus Vaccinium, of which 20 are indigenous to North America, one of these, the European blueberry, or common bilberry (V. myrtillus), growing on acidic soils in western North America, parts of northern Asia, and across Europe. Finally, the Korean blueberry (V. koreanum) is restricted to Korea and the neighbouring Liaoning Province of China.



Jylland 1991-95
Picking delicious blueberries is a popular pastime in many parts of the world, in this case European blueberry, or common bilberry, Jutland, Denmark. (Photo copyright © by Kaj Halberg)






The Nilgiri Mountains constitute a part of the Western Ghats, a mountain range, which stretches most of the way along the west coast of India, from Goa southwards to the southern tip of the subcontinent. The highest point in the Nilgiris is Dodabetta (2637 m).

The name Nilgiri is derived from the Tamil nila (’blue’) and kurinji, which is the name of a blue-flowered plant of the acanthus family (Acanthaceae), Phlebophyllum kunthianum, which only blooms at intervals of 12 years, but so profusely that entire mountain slopes become bluish. By the British, nilakurinji was corrupted to nilgiri, which means ’blue hill’ in Hindi, i.e. more or less the same meaning.

Towards the end of the 1800s, a narrow-gauge railway track was constructed, heading out from the small town of Mettupalayam in the state of Tamil Nadu, leading up through the Nilgiri Mountains and terminating at the hill station Ootacamund (Ooty). This steep railway is operated by a small blue steam train, the Nilgiri Mountain Express.

Over a distance of 46 km, the terrain rises from c. 300 to c. 2,200 m altitude, the tracks passing through 16 tunnels, and across 31 larger and c. 200 smaller bridges. The lower mountain slopes are covered in tropical monsoon forest, and this area is full of waterfalls. Above c. 1,400 m, the forest gives way to plantations of tea, pines, and eucalyptus.



Sydindien 2000-01
Bluish morning mist envelops a eucalyptus plantation in the Nilgiri Mountains, but, as the text above relates, this is not the reason why these mountains got their name. – Eucalyptus is described on the page Plants: Plants in folklore and poetry. (Photo copyright © by Kaj Halberg)



Sydindien 2000-01
In this picture, the Nilgiri Mountain Express is puffing its way up into the Nilgiri Mountains. (Photo copyright © by Kaj Halberg)



Passengers have disembarked during a break at a tiny mountain station. (Photo copyright © by Kaj Halberg)






Pittas are colourful birds of Asia, Australia, and Africa, constituting a separate family, Pittidae, with 40-42 species, divided into three genera, Pitta, Erythropitta, and Hydrornis. They belong to a clade of passerines, called suboscines, which differ from the true songbirds, the oscines, in the syrinx musculature, making their song less varied than that of the oscines.


The gorgeous African pitta (Pitta angolensis) breeds in tropical forest in several areas of West Africa and in south-eastern Africa, from central Tanzania southwards to Mozambique. The south-eastern populations are migratory, spending the southern winter in countries further north, including Uganda, Kenya, and the Central African Republic.



Tanzania 1989
Bright blue rump feathers of an African pitta, Rondo Forest, southern Tanzania. (Photo copyright © by Kaj Halberg)






Ipomoea is a huge genus of the morning-glory, or bindweed, family (Convolvulaceae), 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 Carolus Linnaeus (1707-1778), also called Carl von Linné, in allusion to the worm-like movements of the stem, twining around other plants, fences, etc.

The morning-glory family is described in detail on the page Plants: Morning-glories and bindweeds.


The blue morning-glory (Ipomoea nil) – also called ivy morning-glory due to the shape of its leaves – is probably native to Mexico or Central America, but has been introduced to most warmer parts of the world, where it has become naturalized in many places. Flowers of this species are various shades of blue, with a white funnel. It can be told from similar species by the base of its calyx, which is hairy.



This picture is from Taiwan, where blue morning-glory is very common. (Photo copyright © by Kaj Halberg)



Nepal 2009-2
Blue morning-glory, entwining a species of mugwort (Artemisia), Lower Marsyangdi Valley, central Nepal. (Photo copyright © by Kaj Halberg)






The Blue Nile originates in Lake Tana in the Ethiopian Highlands, from where it makes its way c. 1,500 km to Khartoum, in the Sudan, where it joins the larger White Nile. The name Blue Nile is in fact a misnomer. During the summer monsoon, this river washes down huge amounts of soil from the highlands, which turns its water almost black. In a local Sudanese language, the word for black is also used for blue, so, in reality, the river should be called ‘The Black Nile’.

The first written account of the Blue Nile is from 1565, when a Portuguese, João Bermudes – who called himself Patriarch of Ethiopia – provided a description of the Blue Nile Falls, Tississat, in his memoirs.

Incidentally, to many Christian Ethiopians, the Blue Nile is identified as the sacred river Gihon, one of the four rivers flowing out from the Garden of Eden, as related in Genesis, 2:13.



Ethiopien 1996
Ethiopien 1996
The great Tississat Falls on the Blue Nile, Ethiopia. (Photos copyright © by Kaj Halberg)






The white-winged dove (Zenaida asiatica) is a striking bird, displaying crescent-shaped white wing-patches, black flight-feathers, and a bright blue patch of naked skin around the eye. Despite its specific name asiatica, meaning ‘from Asia’, this dove is a New World bird, distributed in south-western United States, Mexico, Central America, and the Caribbean.

Presumably, Swedish naturalist Carolus Linnaeus (1707-1778), also called Carl von Linné, who named this bird Columba asiatica in 1758, was told that the type specimen originated in Asia. The generic name was introduced in 1838 by French ornithologist Charles Bonaparte (1803-1857), 2nd Prince of Canino and Musignano, in honour of his wife Zénaïde (1801-1854).

There are seven species of smallish doves in this genus, distributed from southern Canada southwards to southern South America.



USA 1992
White-winged dove, photographed near Tucson, Arizona. (Photo copyright © by Kaj Halberg)






Gentians proper, Gentiana, are a huge genus, comprising c. 360 species. It used to contain c. 635 species, but certain authorities, such as the Angiosperm Phylogeny Group System (APG IV), split out c. 23 species of fringed gentians (Gentianopsis), with ciliate margins to the petals, and c. 250 species of dwarf gentians (Gentianella), which, as opposed to Gentiana, are without scales or lobules between the corolla-lobes, while some species have hairs or lobes in the throat.

Members of these genera are distributed almost worldwide, found in Europe, north-western Africa, Asia, the Americas, eastern Australia, and New Zealand. The flowers of most species are various shades of blue, while others are purple, violet, mauve, yellow, white, or, rarely, red. The four or five petals are usually fused, forming a trumpet-, funnel-, or bell-shaped flower.

The name gentian derives from King Gentius, who ruled in Ancient Illyria 181-168 B.C., and who allegedly discovered the medicinal value of the yellow gentian (Gentiana lutea). Its medicinal usage is related on the page Traditional medicine.

The following 8 pictures show various blue gentian species.


The marsh gentian (Gentiana pneumonanthe) grows in marshes and moorlands, from southern Scandinavia southwards to Portugal, Spain, Italy, Albania, and Bulgaria, and from Britain eastwards to Russia and the Caucasus. Formerly, a blue dye was made from the flowers of this species. Incidentally, it is the host plant of a species of butterfly, the Alcon blue (Phengaris alcon).



Fanø 2001-12
Marsh gentian, photographed on the Danish island of Fanø, Jutland. (Photo copyright © by Kaj Halberg)




Clusius’ gentian (Gentiana clusii) is distributed in montane areas of southern Europe, in the Pyrenees, the Alps, the Apennines, the Jura, the Black Mountains, and the Carpathians. It was named after Charles de l’Écluse (1526-1609), also called Carolus Clusius, a Flemish physician and botanist, who was among the first to study the Alpine flora.



Alperne 2016a
Clusius’ gentian, Col du Bous, Marmolada, Dolomites, Italy. (Photo copyright © by Kaj Halberg)




Trumpet gentian (Gentiana acaulis) is very similar to Clusius’ gentian and has a similar distribution, but as opposed to that species, trumpet gentian has longish, green blotches on the corolla, and it prefers to grow on acid soils, whereas Clusius’ gentian is partial to limestone.



Trumpet gentian, Vrata Valley, Triglavski National Park, Slovenia. (Photo copyright © by Kaj Halberg)




Spring gentian (Gentiana verna) is one of the most widespread gentians, distributed across western and southern Europe, in Morocco, Turkey, the Caucasus, and north-western Russia, eastwards to Lake Baikal, the Altai Mountains, and north-western Mongolia. It grows in sunny places at medium altitudes, in the Alps up to c. 2,600 m.



Spring gentian, Grossglockner, Austria. (Photo copyright © by Kaj Halberg)




Short-leaved gentian (Gentiana brachyphylla) is quite similar to spring gentian, but as its name implies, its leaves are very short, only about 1 cm long. This species has a wide distribution in southern Europe, from the Spanish Sierra Nevada and the Pyrenees, eastwards across the Alps to the Carpathians, found at altitudes between 1,800 and 3,100 m.



Alperne 2016a
Short-leaved gentian, Grossglockner, Austria. Purple saxifrage (Saxifraga oppositifolia) is also seen in the picture. (Photo copyright © by Kaj Halberg)




As its specific name implies, Gentiana ornata is a beautiful species, found in the Himalaya, from central Nepal eastwards to south-western China. Like many gentian species, it is flowering late in the year, from September to November.



Nepal 2009
Gentiana ornata, photographed at an altitude of c. 4,200 m, Langtang National Park, central Nepal. (Photo copyright © by Kaj Halberg)




Dwarf gentians, of the genus Gentianella, can be told from other gentians by their flowers, which have lobes or tufts of hair in the throat, and no scales, or lobules, between the corolla-lobes. G. moorcroftiana is distributed in the western parts of the Himalaya, from Pakistan eastwards to central Nepal. It is very common in the drier landscapes of Lahaul and Ladakh, northern India.



Lahaul-Ladakh 2014
Gentianella moorcroftiana, observed near Lake Deepak Tal, Lahaul, India, at an altitude of c. 3,800 m. (Photo copyright © by Kaj Halberg)




Fringed gentians, of the genus Gentianopsis, are identified by their ciliate margins to the petals. The common fringed gentian (G. ciliata), is distributed in southern Europe and western Asia, eastwards to the Caucasus.



Frankrig-Spanien 2007
Common fringed gentian, photographed near Col d’Aubisque, Pyrenees, France. (Photo copyright © by Kaj Halberg)






Stachytarpheta is a genus of about 125 species of shrubby herbs of the vervain family (Verbenaceae). The Jamaica vervain (S. jamaicensis), which is also known by many other names, including blue porterweed, blue snakeweed, bastard vervain, and Brazilian tea, is native from south-eastern United States and Mexico southwards through Central America and the Caribbean to Ecuador and northern Brazil. However, it has been introduced to many other parts of the world and has become naturalized in numerous areas.

This plant is found from sea level to an altitude of about 900 m, growing in open areas, including beaches, along roads, and in fallow fields. It is used medicinally as a cooling agent and blood cleanser, and has also been utilized for treatment of asthma and stomach ulcers.



Taiwan 2014b
This Jamaica vervain is making its way up through a fern leaf, near Nanzen Lake, Kenting National Park, Taiwan. (Photo copyright © by Kaj Halberg)






Elders (Sambucus) is a genus of about 27 species of smaller trees, shrubs, or large herbs, distributed mainly in temperate and subtropical areas of the Northern Hemisphere, whereas on the Southern Hemisphere they are restricted to parts of Australia and South America. Previously, this genus was classified as belonging to the elder family (Sambucaceae), but was then moved to the honeysuckle family (Caprifoliaceae). However, recent DNA analyses have revealed that, in fact, it belongs to the moschatel family (Adoxaceae).

The generic name is from the Greek sambuca, the name of an ancient string instrument of Asian origin. The wood of elder was presumably used in its construction. The name elder is derived from the Anglo-Saxon word aeld (’fire’). In those days, the hollow stems of elder were used to kindle a fire.


Blue elderberry (Sambucus cerulea), formerly often called Mexican elderberry (S. mexicana), is a deciduous shrub, which can grow to a height of 9 m. In spring, it displays an abundance of butter-yellow flowers, followed by purplish-blue berries in autumn. It grows up to an altitude of 3,000 m, in a variety of habitats, including river valleys, woodlands, and exposed slopes with access to water. It has a very wide distribution, from British Columbia south through much of western United States to north-western Mexico, with scattered occurrence in Oklahoma and Texas.

Many indigenous tribes used the berries of this plant for food, and a number of herbal medicines were produced from the wood, bark, leaves, flowers, and roots. The wood was also used to make pipes and musical instruments, such as flutes and small whistles. A dye was made from the berries.



Californien 2011
Blue elderberry is named after its whitish-blue berries. – Yosemite National Park, Sierra Nevada, California. (Photo copyright © by Kaj Halberg)






Meconopsis is a genus of gorgeous poppies, comprising c. 43 species, almost all of which are found in China and the Himalaya. This attractive genus, popularly called Himalayan poppies, is related in depth on the page In praise of the colour yellow.

A number of Meconopsis species have blue petals. Two of these are presented below.



Everest 2010
Meconopsis simplicifolia is easily identified by its largely undivided leaves. This species is found from Nepal eastwards to Bhutan and south-eastern Tibet, here photographed in the Gokyo Valley, Khumbu, eastern Nepal. (Photo copyright © by Kaj Halberg)



Himachal Pradesh 2007
Meconopsis aculeata grows between 3,000 and 4,200 m altitude, from Pakistan eastwards to Uttarakhand, northern India, and extreme south-western Tibet. This picture is from Great Himalayan National Park, Himachal Pradesh, India. (Photo copyright © by Kaj Halberg)






Formerly, Jerdon’s leafbird (Chloropsis jerdoni), which is distributed in the Indian Subcontinent, was regarded as a subspecies of the more widespread blue-winged leafbird (C. cochinchinensis). However, it differs in morphology, lacking the blue flight feathers of the latter. The specific and popular names commemorate British physician and naturalist Thomas Caverhill Jerdon (1811-1872) who described many birds species in India, several of which are named after him.



Indien 2003
This male Jerdon’s leafbird, which can be told from the female by its black throat and blue moustachial stripe, was caught in a mistnet to be ringed, near Mysore, Karnataka, South India. (Photo copyright © by Kaj Halberg)






Baby blue-eyes (Nemophila menziesii) is a gorgeous member of the borage family (Boraginaceae), native to near-coastal areas of western United States and Mexico, from Oregon southwards to Baja California. This plant is widely cultivated as an ornamental and comes in many colour varieties.

The specific name was given in honour of Scottish naturalist Archibald Menzies (1754-1842), who participated, as surgeon and botanist, in an expedition around the world on board HMS Discovery, under the leadership of Captain George Vancouver (1757-1798).



Californien 2013b
Baby blue-eyes, Ronald W. Caspers Wilderness Park, Santa Ana Mountains, California. (Photo copyright © by Kaj Halberg)






The flowerheads of chicory (Cichorium intybus) unfold in the morning, after which they turn, always pointing toward the sun, until around noon. They then wither. A German name of the plant is Wegwarte (’waiting at the road’). A legend has it that the chicory is a transformed virgin, standing at the road side, looking for her sweetheart, turning this way and that.

You may read more about chicory on the page Plants: Plants in folklore and poetry.



Jylland 2006-12
Close-up of a flowerhead of chicory with a male long hover fly (Sphaerophoria scripta), Djursland, Denmark. (Photo copyright © by Kaj Halberg)






The chaffinch (Fringilla coelebs) breeds all over Europe, with the exception of Iceland and far northern Norway and Russia. It is also found on the Azores, Madeira, and the Canary Islands, in North Africa, Turkey, northern Iran, and western Turkmenistan, and in Russia eastwards to central Siberia. It has also been introduced to New Zealand and South Africa.

The male is a pretty bird, with reddish breast and belly, bluish-grey head and nape, olive-green or brownish back and scapulars, and black wings with two conspicuous white bars. The female is greyish-brown, also with white wing bars. Males of the various subspecies in North Africa and on the Atlantic islands are much more bluish, and some authorities speculate that they might constitute several separate species.



Chaffinches were introduced to New Zealand in the 1860s, and several times later. Today, it is very common all over the country. This male was encountered at Lake Tikitapu. (Photo copyright © by Kaj Halberg)




On the Canary Islands, another species of chaffinch, the aptly named blue chaffinch (Fringilla teydea), lives in pine forests on the island of Tenerife – and nowhere else.



Male blue chaffinch, photographed in pine forest on the slopes of the Teide Volcano, Tenerife. (Photo copyright © by Kaj Halberg)






Condensed exhaust from a jet plane draws white lines across a bright blue sky behind smoking chimneys of a fish smokehouse, Hasle, Bornholm, Denmark. (Photo copyright © by Kaj Halberg)






Bluewing, or wishbone flower (Torenia violacea), is a pretty flower of the family Linderniaceae. This species has a very wide distribution in warmer parts of Asia, from India eastwards to southern China and Taiwan, and thence southwards to Indonesia.



Taiwan 2010
This picture is from Taiwan, where bluewing is very common on the lower mountain slopes. (Photo copyright © by Kaj Halberg)






Lahaul-Ladakh 2014
The bright blue T-shirt of this salesman in Pandoh, Himachal Pradesh, northern India, stands out against the subtler colours of the vegetables and fruits around him, including bananas, tomatoes, cucumbers, cabbages, eggplants, and potatoes. (Photo copyright © by Kaj Halberg)






Larkspurs (Delphinium) are a genus in the buttercup family (Ranunculaceae), identified by their irregular flowers, which have five coloured sepals, the upper one with a large, back-pointing spur, and four inner petals, of which the upper two have nectar-producing spurs that are enclosed in the larger spur.

More larkspur species are presented on the pages Plants: Himalayan flora, and Tibetan flora.



A large growth of the dark-blue Delphinium kamaonense, Langtang National Park, Nepal. A species of aster is also seen. (Photo copyright © by Kaj Halberg)






The city of Jodhpur, Rajasthan, north-western India, was founded in 1459 by Rajput Prince Rao Jodha. The Old Town is aptly called ‘The Blue City’, as most of its houses are painted a light blue. Originally, these blue houses were inhabited by Brahmins, and their colour indicated that here you could ask advice about disease as well as religious issues. Furthermore, the blue paint contains copper oxides, which keep termites at bay.



Blue houses in Jodhpur. (Photos copyright © by Kaj Halberg)






Taiwan 2014b
This fishing vessel is in dock, to be furnished with new paint, Wushe Fishing Harbour, north-eastern Taiwan. (Photo copyright © by Kaj Halberg)






Myosotis is a genus of about 74 species with predominantly pale-blue flowers, belonging to the borage family (Boraginaceae). Its common names include forget-me-not and scorpion grass. The name forget-me-not was first used in English by King Henry IV in 1398 – a direct translation of the German word Vergissmeinnicht. A German legend relates that a courting couple was walking along the bank of the River Danube. The young man noticed some beautiful blue flowers, growing in the water near the shore, but as he waded out to pick them for his darling, he was swept away by the strong current. Before he disappeared, he managed to shout: ”Forget me not!”



Sjælland 2006-11
Water forget-me-not (Myosotis scorpioides), photographed on the island of Zealand, Denmark. (Photo copyright © by Kaj Halberg)






The blue pine (Pinus wallichiana) is distributed in montane areas from Afghanistan and the Himalaya eastwards to south-western China. The name of this pine stems from its needles, which have a bluish tinge. In Nepal, honey dew from aphids living on the needles is eaten as candy.

This species is presented in detail on the page Traditional medicine.



Early in the morning, blue pines stand out as silhouettes against the snow-clad peak of Annapurna II (7,937 m), central Nepal. (Photo copyright © by Kaj Halberg)






The blue glassy tiger (Ideopsis vulgaris) is a butterfly in the brush-footed butterfly family, Nymphalidae, subfamily Danainae, whose members are popularly known as monarchs, crows, and tigers. This species is distributed from India eastwards to Taiwan, and thence southwards to Indonesia.



Taiwan 2014b
Blue glassy tiger, feeding in flowers of a species of boneset, Eupatorium schimadae, north-eastern Taiwan. (Photo copyright © by Kaj Halberg)






The gorgeous waterlilies (Nymphaea) are a genus of about 50 species, widespread around the world. The generic name is derived from the Greek nymphe (’nymph’). According to legend, a water-living nymph was deeply in love with the powerful hero Heracles (in Latin called Hercules), who, however, did not return her love. She languished and died, and from her body rose the beautiful waterlily.


The blue waterlily (Nymphaea caerulea), often popularly called Nile lotus or sacred blue Lily-of-the-Nile, is distributed in most of eastern Africa, from Egypt southwards to South Africa.



Tanzania 1990
An abundance of blue waterlilies, covering the surface of a pond near Tanga, northern Tanzania. (Photo copyright © by Kaj Halberg)






The marvellous Sultan Ahmet Camii (Sultan Ahmet Mosque) in Istanbul, Turkey, popularly known as ‘The Blue Mosque’, was constructed between 1609 and 1616, during the rule of Sultan Ahmet I.



Tyrkiet 2006
Fountain in front of Sultan Ahmet Camii, Istanbul. (Photo copyright © by Kaj Halberg)






The name of borage (Borago officinalis), which has given name to the entire family Boraginaceae. is possibly from the Arabic ʾabū min al-ʿaraq, meaning ‘father of sweat’, which, like the specific name officinalis, refers to the medicinal properties of this species. Its leaves and flowers are excellent in salads. The leaves, which have a cucumber-like smell and taste, are also eaten as a vegetable, or used in soups.

The medicinal usage of borage is dealt with on the page Traditional medicine.



Borage is very common on the Greek island of Crete, where these pictures were taken. (Photos copyright © by Kaj Halberg)






The great Buddhist Bodhnath Stupa, Kathmandu, Nepal, decorated with numerous Tibetan prayer flags, on which mantras are printed. These flags are always placed in the following order: blue, white, red, green, and yellow. When they flutter in the wind, the mantras are dispersed into space, for the benefit of humankind.

You may read more about stupas, prayer flags, and other aspects of Buddhism on the page Religion: Buddhism.



Nepal 2009-2
From the great Bodhnath Stupa in Kathmandu, Nepal, the all-seeing, blue eyes of the Buddha survey the surroundings. (Photo copyright © by Kaj Halberg)






Blue Mesa is an area in Petrified Forest National Park, Arizona, which consists of thick layers of grey, blue, purple, and green mudstone, deposited approximately 220 million years ago.



USA 1992
Blue Mesa, Petrified Forest National Park, Arizona. (Photo copyright © by Kaj Halberg)






Redstarts (Phoenicurus) are a genus of birds, belonging to the flycatcher family, Muscicapidae. Formerly, this genus contained 11 members, but following DNA analyses of two species of the genus Rhyacornis and one species of the genus Chaimarrornis, these are now included in Phoenicurus.


Occupying a wide range of habitats, such as forest clearings, shrubberies, and villages, the blue-fronted redstart (Phoenicurus frontalis) is the commonest among the ten species of redstart, which have been encountered in the Himalaya.



Male blue-fronted redstart, observed in the Annapurna area, central Nepal. (Photo copyright © by Kaj Halberg)




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(Latest update March 2020)