French botanist André Michaux is the first recorded authority to provide a scientific name for the plant, calling it Viburnum opulus var. Pimina or Viburnum trilobum var. edule in 1803. The name edule is derived from the latin word ĕdūlis, meaning edible. The name Pimina refers to the common name for the plant used in Canada at the time. French naturalist Constantine Samuel Rafinesque observed the plant later in 1808, calling it Viburnum edule, V. opulus var. of Michaux. Lacking communication and consensus between naming authorities resulted in further names being provided for the same plant, the most popular being Viburnum pauciflorum. The discrepancy was eventually resolved, and the name Viburnum edule became the commonly accepted scientific name that is still in use today.
Viburnum edule was originally categorized as a member of the Caprifoliaceae (honeysuckle) family, however phylogenetic analysis has caused the plant to be re-classified as a member of the Adoxaceae (moschatel) family.


Squashberry can be found growing in moist soils of various forested regions. It is also found growing in dense areas of trees and shrubs, alongside wetlands and bodies of water, and at higher elevations on gravel banks. The ideal type of soil for Viburnum edule is moist alluvial soil that has good drainage. This plant is dispersed through animals, such as birds and mammals, that carry, eat, digest, and excrete the seeds in different areas. Squashberry is distributed across Canada, all throughout Alaska, and in northern states of the USA. Specifically, it can abundantly be found in the following regions: the Yukon, northern Quebec, western District of Mackenzie to James Bay, south Newfoundland to Oregon, Idaho, Colorado, Minnesota and Pennsylvania. It will be found either as a dominant or codominant understory plant of coniferous forests. Oftentimes, squashberry grows abundantly in Picea glauca (white spruce) forests. Squashberry is also known to be an important pioneer species that grows early after forest fires.


The tart fruit is commonly consumed fresh, however it can also be used to prepare foods such as jams and jellies. Many animals consume the wild berries as a part of their diet, while smaller animals can use the plant as shelter.
Multiple parts of the Viburnum edule plant have been used in herbal medicine. The berries can be used to prepare herbal cough medicines, while the roots have been used to make tea for relief of tooth pain or a sore throat. The twigs of the plant can be chewed or gargled as a tea to also treat sore throat. Lip sores have been treated by massaging the closed flower buds of V. edule on the lips. Modern research efforts have found that the fruit contains high levels of antioxidants.
Numerous Indigenous peoples have traditionally used the plant. The Nuxalk people from the Bella Coola region of British Columbia utilize the berries for food due to the plant's rapid growth rate and high berry production. Notably, a single Viburnum edule shrub can produce a yield of up to 100 berries. Multiple First Nations groups on the northwestern coast of North America have cultivated Viburnum edule plants, planting them in wild forest gardens. Consumption of the berries was mentioned in multiple origin myths of the Haida people, often depicted as the food eaten at feasts or consumed by supernatural beings. Inuit peoples near the Nain settlement in Newfoundland and Labrador are also known to traditionally collect the wild fruits.


Viburnum lantana, the wayfarer or wayfaring tree, is a species of Viburnum, native to central, southern and western Europe (north to Yorkshire in England), northwest Africa, and southwestern Asia. The vigorous deciduous European treelike shrub is common along waysides.


It is a deciduous shrub or small tree growing to 4–5 m (13–16 ft) tall. The leaves are opposite, simple oval to lanceolate, 6–13 cm (2.4–5.1 in) Long and 4–9 cm (1.6–3.5 in) broad, with a finely serrated margin; they are densely downy on the underside, less so on the upper surface. The hermaphrodite flowers are small, around 5 mm (0.20 in), and creamy-white, produced in dense cymes 4–10 cm (1.6–3.9 in) width at the top of the stems; they are produced in early summer, and pollinated by insects. The fruit is an oblong drupe 8 mm (0.31 in) long, green at first, turning red, then finally black at full maturity, and contains a single seed. The seeds are dispersed when birds eat the fruit, then deposit the seeds in another location in their droppings.
An older name for the plant is hoarwithy. "Hoar" means grey-haired and refers to the hairs under the leaves, and "withy" means a pliant stem.


It is commonly grown as an ornamental plant for its flowers and berries, growing best on alkaline soils. A number of cultivars have been selected, including 'Aureum', with yellow leaves in spring.
The fruit is mildly toxic, and may cause vomiting or diarrhea if consumed in large quantities.


Viburnum lentago, the nannyberry, sheepberry, or sweet viburnum, is a species of Viburnum native to North America.


It is a large shrub or small tree growing upwards to 9 m (30 ft) tall with a trunk up to 25 cm (10 in) in diameter and a short trunk, round-topped head, pendulous, flexible branches. The bark is reddish- to grayish-brown, and broken into small scales. The twigs are pale green and covered with rusty down at first, later becoming dark reddish brown, sometimes glaucous, smooth, tough, flexible, and produce an offensive odor when crushed or bruised. The winter buds are light red, covered with pale scurfy down, protected by a pair of opposing scales. Flower-bearing buds are 2 cm (3⁄4 in) long, obovate, long pointed; other terminal buds are acute, 8.5 to 12.7 mm (1⁄3 to 1⁄2 in) long, while lateral buds are much smaller. The bud scales enlarge with the growing shoot and often become leaf-like.
Like all viburnums, the leaves are arranged in opposite pairs on the twigs; they are oval, 5–10 cm (2–4 in) long and 2–5 cm (3⁄4–2 in) broad, wedge-shaped, rounded or subcordate at base, with an acuminate apex and a finely serrated margin, and a winged petiole. They open from the bud involute, bronze green and shining, hairy and downy; when full grown are bright green and shining above, pale green and marked with tiny black dots beneath. In autumn they turn a deep red, or red and orange.
The flowers are small, 5–6 mm (0.20–0.24 in) in diameter, with five whitish petals, arranged in large round terminal cymes 5–12 cm (2–4+3⁄4 in) in diameter; flowering is in late spring. The calyx is tubular, equally five-toothed, persistent; the corolla is equally five-lobed, imbricate in the bud, cream-white, one-quarter of an inch across; lobes acute, and slightly erose. There are five stamens, inserted on the base of the corolla, alternate with its lobes, exserted; filaments slender; anthers bright yellow, oblong, introrse, versatile, two-celled; cells opening longitudinally. The pistil has a one-celled inferior ovary, the style thick, short, light green, and the stigma broad; there is one ovule in each cell. The fruit is a small round blue-black drupe, 8–16 mm (0.31–0.63 in) long on a reddish stem; it is thick-skinned, sweet, and rather juicy. The stone is oblong oval, flattened.
The roots are fibrous. The wood is ill-smelling, dark orange brown, heavy, hard, close-grained, with a specific gravity of 0.7303.


Nannyberry is native to the northeastern and midwestern United States, and to southern Canada from New Brunswick west to southeastern Saskatchewan. Isolated populations are found in the Dakotas, Wyoming, Colorado, and the Appalachian Mountains as far south as Kentucky and Virginia. It grows in wet soil along the borders of the forest, often found in fence corners and along roadsides.


Mammals, game birds and songbirds consume the fruit during the winter.


As suggested by the alternative name sweet viburnum, the fruit is (unlike that of many viburnums) edible. The bark and leaves were also used by Native Americans in the preparation of herbal medicines.
It is admired for its compact habit, its lustrous foliage which insects rarely disfigure, its beautiful and abundant flowers, its handsome edible fruit and its brilliant autumnal color. It readily adapts itself to cultivation, and is one of the best of the small trees of eastern America for the decoration of parks and gardens in all regions of extreme winter cold. It is easily raised from seeds which, like those of the other American species, do not germinate until the second year after they are planted.
It has been hybridized with Viburnum prunifolium in gardens to give the hybrid Viburnum × jackii.


Viburnum opulus, the guelder-rose or guelder rose (/ˈɡɛldər/) is a species of flowering plant in the family Adoxaceae (formerly Caprifoliaceae) native to Europe, northern Africa and central Asia.


Viburnum opulus is a deciduous shrub growing to 4–5 m (13–16 ft) tall. The leaves are opposite, three-lobed, 5–10 cm (2–4 in) long and broad, with a rounded base and coarsely serrated margins; they are superficially similar to the leaves of some maples, most easily distinguished by their somewhat wrinkled surface with impressed leaf venation. The leaf buds are green, with valvate bud scales.
The hermaphrodite flowers are white, produced in corymbs 4–11 cm (2–4 in) in diameter at the top of the stems; each corymb comprises a ring of outer sterile flowers 1.5–2 cm in diameter with conspicuous petals, surrounding a center of small (5 mm), fertile flowers; the flowers are produced in early summer, and pollinated by insects. The fruit is a globose bright red drupe 7–10 mm diameter, containing a single seed. The seeds are dispersed by birds.


The common name 'guelder rose' relates to the Dutch province of Gelderland, where a popular cultivar, the snowball tree, supposedly originated. Other common names include water elder, cramp bark, snowball tree, common snowball, and European cranberrybush, though this plant is not closely related to the cranberry. Some botanists also include the North American species Viburnum trilobum as V. opulus var. americanum Ait., or as V. opulus subsp. trilobum (Marshall) Clausen.


Viburnum opulus is a member of the Viburnum genus which contains 160 to 170 species. It is classified in the subsection Opulus, which usually contains 5 species. Phylogenetic analyses suggest the following relationship between those species:


Viburnum opulus is grown as an ornamental plant for its flowers and berries, growing best on moist, moderately alkaline soils, though tolerating most soil types well. Several cultivars have been selected, including 'Roseum', in which all the flowers are only of the larger sterile type, with globular flower heads.
The shrub is also cultivated as a component of hedgerows, cover plantings, and as part of other naturalistic plantings in its native regions.
It is naturalised in North America.
The cultivars 'Notcutt’s Variety', 'Roseum' and the yellow-fruited 'Xanthocarpum' have gained the Royal Horticultural Society's Award of Garden Merit.


The fruit is edible in small quantities, with a very acidic taste; it can be used to make jelly. It is however mildly toxic, and may cause vomiting or diarrhea if eaten in large amounts.
The term 'cramp bark' is related to the bark's ability to reduce smooth muscle tightness. Relieving this type of muscle tightness is most often associated with relieving menstrual (period) cramps. However, the bark can also be used during pregnancy for cramps or pain and general muscle cramping.


Mentions of the viburnum can be found throughout Ukrainian folklore such as songs, decorative art, Ukrainian embroidery, and poetry. Its symbolic roots can be traced to the Slavic paganism of millennia ago. According to a legend, kalyna was associated with the birth of the Universe, the so-called Fire Trinity: the Sun, the Moon, and the Star. Its berries symbolize one's home and native land, blood, and family roots. Kalyna is often depicted on Ukrainian embroidery: ritual cloths and shirts. In Slavic paganism kalyna also represents the beauty of a young lady, which rhymes well in the Ukrainian language: ka-ly-na – div-chy-na. The song Chervona Kalyna was the anthem of the Ukrainian Sich Riflemen and the Ukrainian Insurgent Army; along with these national liberating movements in 20th century guelder rose was established as a symbol of riflemen honor, and state independence.
Viburnum opulus (kalina) is also one of the national symbols of Russia. In Russia the Viburnum fruit is called kalina (калина) and is considered a national symbol. Kalina derived in Russian language from kalit' or raskalyat', which means "to make red-hot". The red fiery color of the berries represents beauty in Russian culture and together with sweet raspberries it symbolises the passionate love of a beautiful maiden, since berries were always an erotic symbol in Russia. The bitter side of the red fruit also symbolizes love separation in Russian folk culture. The name of the Russian song Kalinka is a diminutive of Kalina. Viburnum opulus is also an important symbol of the Russian national ornamental wood painting handicraft style called Khokhloma.
In Romanian, which has been influenced by East Slavic culture, Viburnum opulus is called călin. Călin is also used as both a given name and a surname.


Viburnum rafinesqueanum, the downy arrowwood, is a deciduous medium-sized (typically about 2 meters tall) shrub native to the Eastern United States and Canada from Quebec and Manitoba south to Georgia and west to Oklahoma.  Downy arrow-wood produces ornamental but slightly malodorous flowers in Spring.
Viburnum rafinesqueanum has opposite, simple leaves and dark blue fruit in berry-like drupes. Foliage turns orange-red in late fall. Southern arrow-wood (V. dentatum) is similar, except that it blooms later and has broader, more coarsely toothed leaves and longer petioles.
Other similar species are smooth arrowwood (V. recognitum) and Carolina arrowwood (V. carolinianum).


Viburnum rhytidophyllum, the leatherleaf viburnum, is a species of Viburnum, native to Asia.
This vigorous, coarsely textured evergreen shrub has an upright habit and 8-inch (20 cm) long, lustrous, deeply veined oval leaves with dark blue-green surfaces and pale green undersides. The leaf stems are fuzzy brown. In spring, fragrant creamy-white flowers bloom in clusters. Blue berries form in June and become plump through September, maturing to glossy black. Plants grow 10–15 feet (3.0–4.6 m) tall and wide.
The plant is an evergreen shrub or small tree with a suckering habit. The leaves are opposite, crinkled, downy on the underside, less so on the upper surface.


It is commonly grown as an ornamental plant for its evergreen foliage and tolerance of deep shade.


Viburnum rufidulum, also known as the rusty blackhaw, blue haw, rusty nanny-berry, or southern black haw, is a flowering species of shrub or small tree that is common in parts of the Eastern and Central United States. It produces attractive flowers and fall foliage, as well as fruits that are popular with some species of bird.


Leathery deciduous leaves are simple and grow in opposite blades ranging from 0.5-3 inches in length and 1-1.5 inches in width. Petioles are "rusty hairy" with grooves and sometimes wings. Leaf margins are serrate. Autumn leaf colors are bronze to red.
Twigs range in color from "reddish brown to gray"; young twigs are hairy, and get smoother with age.
Bark is similar that of the flowering dogwood, ranging in color from "reddish brown to almost black" and forming "blocky plates on larger trunks".
Viburnum rufidulum blooms in April to May with creamy white flowers that are bisexual, or perfect and similar to those of other Viburnum species, but with clusters as large as six inches wide.
The fruits are purple or dark blue, glaucous, globose or ellipsoid drupes that mature in mid to late summer. The edible fruit has been said to taste like raisins and attract birds.
It is similar to Viburnum prunifolium (blackhaw). Petioles of V. prunifolium do not have the rusty hairs that those of V. rufidulum do.


The rusty blackhaw prefers dry habitats with elevations generally below 750 m.
It grows in Alabama, Arkansas, Florida, Georgia, Illinois, Indiana, Kansas, Kentucky, Louisiana, Mississippi, Missouri, North Carolina, Ohio, Oklahoma, South Carolina, Tennessee, Texas, Virginia, and West Virginia.


It is occasionally used as an ornamental plant.


Vicia caroliniana (common name Carolina vetch, or Carolina wood vetch), is a plant found in North America.


The Cherokee use this plant for a variety of medicinal purposes. It is used for back pains, local pains,  to toughen muscles, for muscular cramps, twitching and is rubbed on stomach cramps. They also use a compound for rheumatism, for an affliction called "blacks", and it is taken for wind before a ball game. An infusion is used for muscle pain, in that it is rubbed on scratches made over the location of the pain. An infusion is also taken as an emetic. It is also used internally with Pseudognaphalium obtusifolium ssp. obtusifolium for rheumatism.


Vicia cracca (tufted vetch, cow vetch, bird vetch, blue vetch, boreal vetch), is a species of vetch  native to Europe and Asia. It occurs on other continents as an introduced species, including North America, where it is a common weed. It often occurs in disturbed habitats, including old fields and roadside ditches.


Vicia cracca is native to Europe and Asia, and has been introduced to large areas of North America.


Recorded as very frequent on waste ground as an introduced species occurring casually. In hedges and waste places.


Vicia hirsuta or Ervilia hirsuta (hairy tare, hairy vetch, tiny vetch) is a species of flowering plant from the large genus Vicia.


It is an annual herb producing a slender, often four-sided, hairless to lightly hairy, climbing stem up to 70 to 90 centimeters tall, and known to well exceed one meter at times. The leaves are tipped with tendrils that support the plant as it climbs, and are made up of up to 10 pairs of elongated leaflets  each up to 2 centimeters in length with notched, flat, sharply pointed, or toothed tips. The inflorescence is a raceme of up to 8 flowers borne near the tip and often on one side only. Each flower is whitish or pale blue, just a few millimeters in length, and short-lived. The fruit is a legume pod up to a centimeter long by half a centimeter wide and hairy, often densely so. It is pale green to nearly black in color and contains usually two seeds.


It is native to Europe and Western Asia. It can be found on other continents as an introduced species. For example, hairy vetch is commonly used in cover crops and green manures on farms in North America. Typically, common vetch or hairy vetch provides the leguminous component of the crop, usually comingled with a grassy component as a nurse crop and an addition of more cellulose to the resultant organic  matter (for example, rye or winter wheat). The species Vicia villosa is also called hairy vetch.


Vicia sativa, known as the common vetch, garden vetch, tare or simply vetch, is a nitrogen-fixing leguminous plant in the family Fabaceae. It is likely native to North Africa, Western Asia and Europe, but is now naturalized in temperate and subtropical regions worldwide. Although considered a weed when found growing in a cultivated grainfield, this hardy plant is often grown as a green manure, livestock fodder or rotation crop. More than 500,000 hectares (1,200,000 acres) per year of Vicia sativa is grown in Australia.


Vicia sativa is a sprawling annual herb, with hollow, four-sided, hairless to sparsely hairy stems which can reach two meters in maximum length.
The leaves are stipulate, alternate and compound, each made up of 3–8 opposite pairs of linear, lance-shaped, oblong, or wedge-shaped, needle-tipped leaflets up to 35 millimeters (1+1⁄2 in) long. Each compound leaf ends in a branched tendril.
The pea-like flowers occur in the leaf axils, solitary or in pairs. The flower corolla is 1–3 centimeters (1⁄2–1+1⁄4 in) long and bright pink-purple in colour, more rarely whitish or yellow. The flowers are mostly visited by bumblebees.
The fruit is a legume pod up to 6 or 7 centimeters (2+1⁄4 or 2+3⁄4 in) long, which is hairy when new, smooth later, then brown or black when ripe. It contains 4–12 seeds.


Sown for fodder, the seed is sown densely, up to 250 kilograms per hectare (220 lb/acre). However, when grown for seed, less seed should be used; otherwise the crop will be too thick, reducing flower and seed production. When meant for seed, sowing is done early in the planting season for good returns; but, when for green manure, any time in spring is suitable. Sometimes, a full crop can be obtained even when sown as late as summer, though sowing so late is not recommended.
After the seed is sown and the land carefully harrowed, a light roller ought to be drawn across, to smooth the surface and permit the scythe to work without interruption. Also, the field should be watched for several days to prevent pigeons from eating too much of the sown seed.
Horses thrive very well on common vetch, even better than on clover and rye grass; the same applies to fattening cattle, which feed faster on vetch than on most grasses or other edible plants. Danger often arises from livestock eating too much vetch, especially when podded; colics and other stomach disorders are apt to be produced by the excessive amounts devoured.
Cereal grains can be sown with vetch so it can use their stronger stems for support, attaching via tendrils. When grown with oats or other grasses, the vetch can grow upright; otherwise its weak stems may sprawl along the ground. Several cultivars are available for agricultural use, and as for some other legume crops, rhizobia can be added to the seed.
Pests that attack this crop include the powdery mildew fungus Erysiphe pisi, the pea aphid Acyrthosiphon pisum, the corn earworm (Heliothis zea), the fall armyworm (Spodoptera frugiperda), and spider mites of genus Tetranychus.
During the early 20th century, a mutant of the common vetch arose with lens-shaped seeds resembling those of the lentil, leading to vetch invasions of lentil fields. D. G. Rowlands showed in 1959 that this was due to a single recessive mutation. The transition from traditional winnowing to mechanised farming practices largely solved this problem.
Improved varieties of Vicia sativa developed by the National Vetch Breeding Program for Australian farmers include; Timok, Volga, Rasina and more recently Studenica. These varieties are mostly cultivated in Western Australia, South Australia and Victoria. More than 500,000 hectares (1,200,000 acres) per year of Vicia sativa was grown in Australia in 2019.


Common vetch has long been part of the human diet, as attested by carbonised remains found at early Neolithic sites in Syria, Turkey, Bulgaria, Hungary and Slovakia. It has also been reported from Predynastic sites of ancient Egypt, and several Bronze Age sites in Turkmenia and Slovakia. However, definite evidence for later vetch cultivation is available only for Roman times.
The "tare" referred to in some English translations of the Bible (as in the "Parable of the Tares") may be darnel ryegrass, Lolium temulentum.


Vicia sativa was first described by Carl Linnaeus in his 1753 Species Plantarum. Since that time, a number of synonyms have published:
Vicia abyssinica Alef.
Vicia alba Moench
Vicia amphicarpa Dorthes
Vicia amphicarpa L.
Vicia angustifolia L.
Vicia angustifolia Reichard
Vicia bacla Moench
Vicia bobartii E. Forster
Vicia bobartii E.Forst.
Vicia bobartii Koch
Vicia canadensis Zuccagni
Vicia communis Rouy
Vicia consobrina Pomel
Vicia cordata Hoppe
Vicia cornigera Chaub.
Vicia cornigera St.-Amans
Vicia cosentini Guss.
Vicia cuneata Gren. & Godr.
Vicia cuneata Guss.
Vicia debilis Perez Lara
Vicia erythosperma Rchb.
Vicia glabra Schleich.
Vicia globosa Retz.
Vicia heterophylla C.Presl
Vicia incisa M.Bieb.
Vicia incisaeformis Stef.
Vicia intermedia Viv.
Vicia lanciformis Lange
Vicia lentisperma auctor ign.
Vicia leucosperma Moench
Vicia macrocarpa Bertol.
Vicia maculata C.Presl
Vicia maculata Rouy
Vicia melanosperma Rchb.
Vicia morisiana Boreau
Vicia nemoralis Boreau
Vicia nemoralis Ten.
Vicia notota Gilib.
Vicia pallida Baker
Vicia pilosa M.Bieb.
Vicia pimpinelloides Mauri
Vicia segetalis Thuill.
Vicia subterranea Dorthes
Vicia terana Losa
Vicia vulgaris Uspensky
There are at least four generally accepted subspecies:
Vicia sativa subsp. cordata (Hoppe) Asch. & Graebn.
Vicia sativa subsp. nigra (L.) Ehrh. – narrow-leaved vetch (= subsp. / var. angustifolia, subsp. consobrina, subsp. cordata (Hoppe) Batt., subsp. cuneata, subsp. heterophylla, var. minor, var. nigra)
Vicia sativa subsp. sativa (= var. linearis, ssp. notata)
Vicia sativa subsp. segetalis (Thuill.) Arcang. (sometimes included in subsp. nigra)


The Vicia sativa karyotype consists of 5, 6 or 7 chromosomes, with six (n=6) being the most common and best described. Given the Vicia sativa's genome is relatively large genome size (1.75Gb) due to large amounts of repetitive DNA, sequencing the genome was challenging compared to other legumes such as Medicago truncatula or soybeans.
A high-quality chromosome level genome assembly was published in 2021 of variety Studencia (n=6), following a draft genome assembly of line KSR5 (n=7). Variety Studencia, is predicted to have 53,318 protein coding genes. Whole genome sequence comparisons showed that Vicia sativa is most closely related to pea.
A high-quality genome sequence facilitates the application of genome editing and genomic selection for healthy, higher yielding varieties.


Vicia sepium or bush vetch is a plant species of the genus Vicia.
A nitrogen-fixing, perennial, leguminous climbing plant that grows in hedgerows, grasslands, the edges of woodland, roadsides and rough ground. It occurs in western Europe, Russia including Siberia, Crimea, Caucasus and Central Asia. It can also be found in eastern Canada, north-eastern states of the USA and, where suitable habitat occurs, in Greenland. It is also found throughout England and eastern parts of Wales.


A rhizomatous plant.  Its climbing habit is enabled by branched tendrils at the end of each leaf stem, which curl around surrounding plants. The stems are not branched, are almost glabrous, sometimes with rare soft hairs, single, mostly 30 to 40 cm long but sometimes as much as 100 cm. The leaves are compound and pinnate with 4 to 8 pairs of opposite leaflets ending in branched tendrils. Leaflets are 20 to 30 mm long, 8 to 10 mm wide, elongated elliptical in form with broad bases and glabrous at both sides. Flower stalks are very short with 2 to 6 almost sessile flowers on each. Flowers are 12 to 15 mm long, reddish-lilac or lilac-blue.  Similar in appearance to common vetch (Vicia sativa) but each stem of the latter has more flowers, and bush vetch is usually hairless whereas V. sativa is slightly hairy.
Flowers between May to August, occasionally into November. Mainly cross pollinated by insects. The resultant pods or legumes ripen mainly during July to August, are 30 to 40 mm long, 6 to 8 mm wide, elongated, rhomboid and black in colour. The seeds within are black or brown.
A good potential forage crop with high nutritional value, characterized by high seed productivity in less favourable years. Can by used for hay or silage, particularly arable silage, from perennial grass-vetch mixtures.
Bush vetch supports a variety of generalist legume feeders including beetles, weevils and caterpillars. Bumblebees and honeybees seek out the flowers for their nectar.


Vicia tetrasperma (syn. Ervum tetraspermum) the smooth tare, smooth vetch, lentil vetch or sparrow vetch, is a species of flowering plant from the large genus Vicia of the legume family Fabaceaae. It can be invasive.


Vicia tetrasperma is an annual plant growing up to 60 cm (24 in) tall. The leaflets are 10 to 20 mm (0.39 to 0.79 in) and are in four to six pairs, the leaf ending with a simple tendril. The pale blue flowers are in racemes of one or two flowers, each about 4 mm (0.16 in) long. Four seeds are produced in a pod 12 to 15 mm (0.47 to 0.59 in) long. The pod is dehiscent.


This vetch is native to Europe, Asia, and North Africa, and it can be found on other continents as an introduced species.


Vicia villosa, known as the hairy vetch, fodder vetch or winter vetch, is a plant native to some of Europe and western Asia. It is a legume, grown as a forage crop, fodder crop, cover crop, and green manure. Although non-native, it occurs in all US states and is considered invasive by some states, such as Alaska, Florida, Georgia, Kansas, Michigan, Minnesota, Oregon, and Washington state — as well as in Japan and some parts of Europe where it is not native. It is also found in most Canadian provinces.
Hairy vetch is very similar to tufted vetch (Vicia cracca), the most noticeable difference being that tufted vetch has a smooth stem.
Several subspecies are recognized:
Vicia villosa ssp. ambigua (Guss.) Kerguelen (= ssp. elegantissima, ssp. pseudocracca)
Vicia villosa ssp. eriocarpa (Hausskn.) P.W.Ball
Vicia villosa ssp. microphylla (d'Urv.) P.W.Ball
Vicia villosa ssp. varia (Host) Corb. (= ssp. dasycarpa)
Vicia villosa ssp. villosa
The species Vicia hirsuta is also called hairy vetch.


Hairy vetch is widely used by organic growers in the United States as a winter cover crop and in no-till farming, as it is both winter hardy and can fix as much as 200 lb/acre of atmospheric nitrogen.  Disadvantages of hairy vetch in production agriculture are related to the crop having a portion of hard seed and its tendency to shatter seed early in the season, leading to it remaining in the field as a weed later in the season.  This can be a particular problem in wheat production.


Organic gardeners often plant hairy vetch (a nitrogen-fixing legume) as a companion plant to tomatoes, as an alternative to rotating crops in small growing areas.  When it is time to plant tomatoes in the spring, the hairy vetch is cut to the ground and the tomato seedlings are planted in holes dug through the matted residue and stubble. The vetch vegetation provides both nitrogen and an instant mulch that preserves moisture and keeps weeds from sprouting.


It is regulated in the state of Florida. Some sources consider it generally invasive in areas with suitable climate for it to out-compete native species, in a manner similar to how cow vetch, Vicia cracca, is regarded. With both vetches, their agricultural usefulness is typically given precedence over concerns regarding potential ecological degradation. Despite being native to part of Europe it is considered an alien or invasive species in some European countries, such as Belgium, the Czech Republic, France, Germany, Italy, Poland, and Spain.


Vincetoxicum nigrum, a species in the family Apocynaceae, also known as black swallow-wort, Louise's swallow-wort, or black dog-strangling vine, is a species of plant that is native to Europe and is found primarily in Italy, France, Portugal, and Spain. It is an invasive plant species in the northeastern United States, parts of the Midwest, southeastern Canada, and California. In 2020, wild plants were found in Timaru, New Zealand.


Vincetoxicum nigrum is a perennial, herbaceous vine bearing ovate leaves with pointed tips. The leaves are 3–4 inches (7.6–10.2 cm) long, and 2–3 inches (5.1–7.6 cm) wide, occurring in pairs on the stem. The flowers have five petals, and are star-shaped with white hairs. The flowers range in color from dark purple to black. The fruit of Vincetoxicum nigrum is a slender, tapered follicle that ranges in color from green through light brown and is tightly packed with seeds, each bearing a fluffy pappus to allow distribution by the wind.


Vincetoxicum nigrum tends to grow in upland areas and is tolerant to variable light, salt, and moisture levels. In the United States, the vine is often found in abandoned fields, hedgerows, brushy areas, woodlands, river banks, transportation corridors, quarries, agricultural fields, and gardens. In gardens, the plant is seen as a fast-growing weed.


Vincetoxicum nigrum emerges from an underground stem in the spring, and flowers during June and July. Vincetoxicum nigrum is self-pollinating, and follicles form throughout the summer. The number of follicles formed is directly linked to the amount of light the plant receives. If there is a lower level of light, then there are fewer follicles compared to a plant exposed to a higher level of light. The seeds begin to be released by mid-August, and continue to be dispersed by air currents into early October.
Each seed is polyembryonic and contains about one to four embryos per seed, increasing Vincetoxicum nigrum's proliferation. Seeds have delicate fibrous "parachutes" used in wind dispersal over long distances. In addition to seeds for reproduction, Vincetoxicum nigrum also uses rhizomes as a method of propagation, meaning that the plant clones itself underground and produces new plants. After seed dispersal, the plant dies to the ground in the winter, reappearing in the spring.


The first sighting of Vincetoxicum nigrum in North America was recorded in Ipswich, Massachusetts in 1854. In 1864, a plant collector recorded that it was "escaping from the botanical garden where it is a weed promising to be naturalized". Vincetoxicum nigrum escaped from a garden in the Cambridge area of Massachusetts and naturalized in the surrounding states and is still spreading today. Massachusetts and New York classify the plant as an invasive species. Beyond the northeastern US, the plant has been reported in Wisconsin and California.


In the United States and Canada, Vincetoxicum nigrum is a threat to native species because it crowds them out. For example, it can completely replace a field of native goldenrod. Crowding out other species results in a reduced habitat for wildlife, which may become endangered because they can no longer find their optimal habitat.
Vincetoxicum nigrum threatens the rare limestone pavement barren ecosystems by crowding out plants that the native wildlife needs to survive. It may also decrease bird presence in grasslands, which may in turn cause certain insect species populations to increase.
In Vermont, Vincetoxicum nigrum crowds out the endangered species Jesup's milk vetch (Astragalus robbinsii var. jesupii). In Rhode Island, Vincetoxicum nigrum has been reported as reducing the effectiveness of electric fences, which may allow livestock to be put into danger or lost.
In addition, Vincetoxicum nigrum crowds out a species of milkweed that monarch butterflies use as their larval food plant. Thus, the spread of this plant threatens populations of monarch butterflies. Overall, Vincetoxicum nigrum reproduces very prolifically, and can easily take over various habitats in a short time. Most of the possible implications of  Vincetoxicum nigrum's changing the structure of various ecosystems have not yet been studied.


There are four methods of management that can possibly be used for the management of Vincetoxicum nigrum. These methods are chemical, manual, mechanical, and biological. Only the chemical, manual, mechanical methods are actually used in the United States and Canada. The biological method may be used in the future. Overall, early detection and removal is the best management strategy.


The best chemical management of Vincetoxicum nigrum is through the use of systemic herbicides which prevent seeds from being viable. Garlon 4 (triclopyr) and  RoundUp Pro (glyphosate) are the main systemic herbicides that are used to control the vine. The systemic herbicide is most effective when sprayed on the plant after flowering has begun. If the herbicide is used after follicles have formed, it is less effective because viable seeds may still form. The most effective treatment using systemic herbicides is through a cut stem application, consisting of applying the chemical to the recently-cut stems of the swallow-wort vines.


Manual management is the removal of Vincetoxicum nigrum from the ground by digging up its rhizomes so that the plant cannot reproduce. The vine has an extensive rhizome system which must be completely removed to prevent new shoots from growing.  Trying to remove the vine by pulling will often cause the plant to detach from its rhizome, allowing the vine to continue to grow new shoots.   Seed pods must be disposed of carefully, to avoid inadvertently spreading the seeds to new areas.


Mechanical management is the mowing down of Vincetoxicum nigrum. This method does not stop growth, but it does stop seed crops. No seed crop means that the plant has no offspring.


Biological management is the use of the vine's natural enemies to stop the spread and diminish the population of Vincetoxicum nigrum.  In the United States, Vincetoxicum nigrum has no natural enemies, but in its native Europe, certain caterpillars, beetles, and diseases attack the plant. Researchers at Cornell University and the USDA have investigated the use of natural enemies as a way to control the plant. The use of natural enemies is controversial, because the implications of adding more non-native species to threatened areas is unknown. In 2014 Hypena caterpillars were released in Ontario, Canada to help control Vincetoxicum's spread.


Viola adunca is a species of violet known by the common names hookedspur violet, early blue violet, sand violet, and western dog violet. It is native to meadows and forests of western North America, Canada, and the northern contiguous United States.


This is a hairy, compact plant growing from a small rhizome system. The leaves are spade- or heart-shaped, sometimes with broadly wavy margins. They are generally 0.5 to 4 centimeters long. The single-flowered inflorescence grows at the end of a very thin peduncle reaching about 7.5 cm (3 in) high. The nodding flower is a violet about 1.5 cm (1⁄2 in) long, with five purple petals. The lower three petals have white bases and purple veining. The two side petals are white-bearded near the throat. The upper two petals may have hooked spurs at their tips. It is a perennial blooming in late spring.
There are several varieties of V. adunca; a white-petaled form has been noted in Yosemite National Park.
It has also been observed in Southern Ontario in tall grass prairies on the sand plain and in black oak savannas.


Viola adunca is the larval host plant of Myrtle's silverspot. Bees and other insects pollinate it. Polites mardon uses it as a nectar source, and birds and mice use the seed as a food source.


The species is listed as endangered in Massachusetts and in Connecticut.


The leaves and flowers are edible, and can be eaten in salads, as potherbs, or brewed as tea. These plant parts are high in vitamins A and C. However, the rhizomes, fruit, and seeds are poisonous to humans and can cause upset stomach, intestinal problems, respiratory and circulatory depression.


Viola arvensis is a species of violet known by the common name field pansy. It is native to Europe, western Asia, and North Africa, and it is known on other continents as an introduced species and a weed of disturbed and cultivated areas.
Viola arvensis was shown to contain cyclotides, a class of peptides found in plants. The peptide cycloviolacin O2 in particular has shown to possess cytotoxic activity against human cancer cells and is therefore looked at as a potential drug lead.


It is an herbaceous annual plant with serrated leaves, and usually flowers with white all over, except the bottom petal (Although there are actually flowers with a tinge of purple at the top) and dehiscent capsules. It reproduces by seed. It grows 20 centimeters tall.


Viola biflora is a species of the genus Viola. It is also called alpine yellow-violet, arctic yellow violet, or twoflower violet.  It is found in Europe, Siberia, Central Asia, Pakistan, western and northern China, North Korea, Japan, and Western North America.


Viola canina (heath dog-violet or heath violet) is a species of the genus Viola, native to Europe, where it is found in heaths, fens, and moist woodlands, especially on acidic soils.
It is a herbaceous perennial plant growing to 5–15 cm tall. The flowers are pale blue, produced from April to July. Colonies of plants may be extensive.
It is host to the pathogenic fungi Puccinia violae and Ramularia lactea.


Viola hirta is a species of the plant genus Viola. It is also called the hairy violet. As with the sweet violet, no fossil seeds of this species have been found. It is confined to the cold temperate zone, in Europe, north and west Asia, extending as far as northwest India. It is absent in Wales from Brecon and Radnor, Pembroke, Cardigan, Merioneth, and from Mid Lancs, and the Isle of Man, but elsewhere it is universal. In Scotland it does not occur in Roxburgh, Berwick, Haddington, Edinburgh, Fife, Forfar, Kincardine. From Forfar it ranges to the south of England, and is found at a height of 1000 ft. in Yorks. It occurs also in Ireland.


The hairy violet is found on dry banks, and in woods, preferring drier conditions. It may be found in damper areas in woods in low-lying situations. This species has a less wide range than sweet violet  (Viola odorata). Note it is considered by some sources to be the same species as Viola odorata.


The habit is prostrate like that of the sweet violet, which also has no erect stem, the leaves arising from the rootstock directly. The leaves are likewise heart-shaped, but in this case the stoles or trailing stems with buds are absent or very short, and the bracts are below the middle of the flower-stalk. Moreover, the whole plant is hairy, or roughly hairy, giving it a greyer, less green, appearance when dry.


Viola labradorica, commonly known as alpine violet, American dog violet, dog violet or Labrador violet, is a perennial herbaceous flowering plant. It is native to Greenland, eastern Canada, and the eastern United States. The plant sold as Viola labradorica by nurseries is Viola riviniana.


Viola labradorica has edible leaves and flowers. The leaves are sometimes characterized as "wooly" and thus not as desirable for eating.


Viola nuttallii (Nuttall's violet or yellow prairie violet) is a perennial herbaceous plant in the violet family (Violaceae), and is one of the few violet species with lanceolate leaves. It is native to the western Canada and the north-central and western United States, appearing in upper steppe lands, forests, and alpine ridges.
The genus name Viola means violet in Latin. For Nuttall's violet the only purple coloring is the nectar guides in the throat of the flower. The species name is given in honor of noted botanist Thomas Nuttall.
The plant is highly variable, usually with bright yellow petals. The veined, elliptical leaves are 2.5–10 centimeters (1–4 in) long.
The species serves as a larval host for the Coronis fritillary butterfly.


Viola ocellata is a species of violet known by the common names pinto violet, two-eyed violet, and western heart's ease. It is native to southern Oregon and northern and central California, where it occurs in the coastal foothills and mountain ranges. It sometimes grows in serpentine soils and in quicksilver mines.


This rhizomatous herb produces a hairy erect or decumbent stem measuring 5 to 37 centimetres (2.0 to 14.6 in) long. The leaves have heart-shaped or roughly lance-shaped blades borne on petioles a few centimeters long. A solitary flower is borne on a long, upright stem. It has five white petals with yellow bases, the lowest three veined with purple and the two lateral ones with purple eyespots. The inside of the flower has long hairs. The outer surfaces, at least of the two upper petals, is usually stained dark red or purple. It capsules are spherical and are 5–11 millimetres (0.20–0.43 in) long while its peduncles are puberulent and are 1–10 centimetres (0.39–3.94 in) long. The seeds of the plant are brownish-purple in colour and are 2 millimetres (0.079 in) long. The rootstocks are often long and stolon-like.
The species is a host plant of the butterfly Boloria epithore.


Viola odorata is a species of flowering plant in the genus Viola, native to Europe and Asia. This small hardy herbaceous perennial is commonly known as wood violet, sweet violet, English violet, common violet, florist's violet, or garden violet. It has been introduced into North America and Australia.


Viola odorata can be distinguished by the following characteristics:
the flowers are scented
the flowers are normally either dark violet or white
the leaves and flowers are all in a basal rosette
the style is hooked (and does not end with a rounded appendage)
the leaf-stalks have hairs which point downwards
the plant spreads with stolons (above-ground shoots)
These perennial flowers mature at a height of 4–6 in (10–15 cm) and a spread of 8–24 in (20–61 cm). The species can be found near the edges of forests or in clearings; it is also a common "uninvited guest" in shaded lawns or elsewhere in gardens.


Several cultivars have been selected for garden use, of which V. odorata 'Wellsiana' has gained the Royal Horticultural Society's Award of Garden Merit.
The sweet scent of this flower has proved popular, particularly in the late Victorian period, and has consequently been used in the production of many cosmetic fragrances and perfumes. The French are also known for their violet syrup, most commonly made from an extract of violets. In the United States, this French violet syrup is used to make violet scones and marshmallows.
The scent of violet flowers is distinctive with only a few other flowers having a remotely similar odor.  References to violets and the desirable nature of the fragrance go back to classical sources such as Pliny and Horace when the name ‘Ion’ was in use to describe this flower from which the name of the distinctive chemical constituents of the flower, the ionones – is derived. In 1923, Poucher wrote that the flowers were widely cultivated both in Europe and the East for their fragrance, with both the flowers and leaves being separately collected and extracted for fragrance, and flowers also collected for use in confectionery galenical syrup  and in the production of medicine.
There is some doubt as to whether the true extract of the violet flower is still used commercially in perfumes. It certainly was in the early 20th century, but by the time Steffen Arctander was writing in the late 1950s and early 1960s, production had "almost disappeared". Violet leaf absolute, however, remains widely used in modern perfumery.
The leaves are edible. Real violet flower extract is available for culinary uses, especially in European countries, but it is expensive.


In herbal medicine, V. odorata has been used for a variety of respiratory ailments, insomnia, and skin disorders.  However, there is insufficient evidence to support its effectiveness for these uses.


V. odorata may be the species mentioned in Shakespeare's famous lines:
"I know a bank where the wild thyme blows,
Where oxlips and the nodding violet grows,
Quite over-canopied with luscious woodbine,
With sweet musk-roses and with eglantine"


Two primary color forms exist, Viola pedata var. lineariloba ("concolor"), which is a solid pink-lilac-lavender color, and var. pedata ("bicolor"), in which the superior petals are a deep red-purple and the lateral and interior petals are similar to the concolor variety.  Less common is Viola pedata var. linearloba forma alba, which is a white flowered form.


Birdsfoot violet favors well drained, acidic soils in full to partial sun environments.  It is difficult to cultivate in typical garden environments because it does not tolerate rich, organic garden soils and excess moisture.


Viola pedatifida, known variously as prairie violet, crow-foot violet, larkspur violet, purple prairie violet, and coastal violet, is a perennial herbaceous plant in the Violet family (Violaceae). It is native to Canada and the United States.


Prairie violet was first formally named in 1831 by the Scottish botanist George Don (1798–1856). The specific epithet pedatifida means "palmately divided with cleft segments" in botanical Latin, in reference to the leaves, which look like a bird's foot with the outer toes again parted.
It may hybridize with the common blue violet, Viola sororia.


Prairie violet grows 5–30 cm (2.0–11.8 in) tall with violet flowers and between 2–11 deeply divided leaves. It is an acaulescent violet, meaning it lacks leaves on the flowering stems. The leaves have 5–9 lanceolate to linear lobes, growing up to 7 cm (2.8 in) long and 8 cm (3.1 in) across. Prairie violet flowers between March and June. The flowers are light violet, the lower three petals white near the base, usually with some hairs. It forms ellipsoid capsules in the summer.


Viola pedatifida is native broadly across the central United States and south-central Canada, from Alberta to Ontario, south to Arkansas, west to New Mexico. It has a disjunct distribution in Virginia where it grows in Appalachian shale barrens. Across much of its range, prairie violet grows in dry prairies and other dry, sunny habitats.


Viola pedunculata, the California golden violet, Johnny jump up, or yellow pansy, is a perennial yellow wildflower of the coast and coastal ranges in California and northwestern Baja California.   The common name "Johnny jump up" is usually associated with Viola tricolor however, the introduced garden annual.
The plant grows on open, grassy slopes, in chaparral habitats, and in oak woodlands, from sea level to around 3,280 feet (1,000 m). It prefers part shade, but will tolerate sun in many locations.


Viola pedunculata  is a perennial, growing from a spongy rhizome. The plant is often low-growing, but can reach a height of 6 inches (15 cm).
The leaves are 1-5.5 cm long, cordate (heart-shaped) to deltate-ovate (oblong-triangular), scalloped or toothed, and glabrous or hairy. They are summer deciduous.
The fragrant flowers appear in March and April, and are a rich, saturated yellow to yellow-orange, with brown-purple nectar guides on the lower petals. The flowers are hermaphrodite, and are pollinated by native and introduced insects.  Dried in air, the seeds weigh about 4 milligrams (0.00014 oz) each.
Subspecies
Viola pedunculata ssp. pedunculata
Viola pedunculata ssp. tenuifolia


The leaves were used by the Diegueno and Luiseno indigenous people of California for food:. The young leaves were picked before the flowers appeared in the spring, then boiled, and used as greens.
The flower buds and petals are edible. As with other yellow flowers in the genus Viola, large quantities may cause diarrhea.
An herbal tea or tisane can be brewed from the leaves.


The plant is cultivated as an ornamental plant by specialty plant nurseries, for planting as a drought tolerant seasonal groundcover or flowering accent plant in native plant and wildlife gardens; and as a potted plant.
They are propagated by seed or nursery/garden divisions. The plant prefers rich soil, and no irrigation water in summer, when it is dormant.
When cultivated in colder climates outside its native range where not so hardy, it is most successful when propagated in a cold frame.


Viola primulifolia, commonly called the primrose-leaf violet, is a species of flowering plant in the violet family. It is native to eastern North America, and possibly also to the Pacific Northwest. Its natural habitat is wet acidic areas that are usually at least semi-open.
It is a low, stemless perennial that produces white flowers in the spring. It can be distinguished from the similar-looking Viola lanceolata and Viola blanda by its leaves that are ovate, with rounded to truncate bases, and are 1.5-2 times as long as wide.
While typical Viola primulifolia occurs in a large area of the east, a variety of this species is sometimes credited to occur in a small area of western California and Oregon, under the name of V. primulifolia var. occidentalis. These populations, which are considered rare and highly localized, have alternatively been referred to as Viola lanceolata ssp. occidentalis.


Viola pubescens, commonly called the downy yellow violet, is a plant species of the genus Viola and is classified within the subsection Nudicaules of section Chamaemelanium. It is a widespread North American violet found in rich, mesic woodlands, and sometimes in meadows, from Minnesota and Ontario east to Nova Scotia and south to Virginia. V. pubescens produces two different types of flowers during the season, including chasmogamous flowers in the early spring and cleistogamous flowers summer through fall.
Similar-looking species include the round-leaved yellow violet (Viola rotundifolia). The two species can be differentiated by leaf shape and leaf margin. Additionally, V. pubescens has both basal and cauline leaves, while V. rotundifolia has only basal leaves.


Viola purpurea is a species of violet which bears yellow flowers. It is known commonly as the goosefoot violet. It is a small plant which bears thick to fleshy toothed or ridged oval leaves which are mostly green but may have a purplish tint to them. The flowers are made up of bright yellow petals, the lowermost being streaked or veined with purple and the lateral petals with purplish undersides.
There are several subspecies, most of which are known by the common name goosefoot violet. These subspecies are found across the western United States from Wyoming to California. It is a member of the chaparral plant community and the foothills and low elevation mountains.


Viola purpurea subsp. charlestonensis , found as high as 8500 ft elevation.
Viola purpurea subsp. dimorpha
Viola purpurea subsp. geophyta
Viola purpurea subsp. integrifolia
Viola purpurea subsp. mesophyta
Viola purpurea subsp. mohavensis
Viola purpurea subsp. purpurea
Viola purpurea subsp. quercetorum
Viola purpurea subsp. venosa, most widely distributed variety.


Viola reichenbachiana, the early dog-violet, or pale wood violet is a flowering plant in the violet family Violaceae.
This species hybridises with Viola riviniana, the common dog-violet, to produce Viola × bavarica Schrank 1789.


Viola riviniana, the common dog-violet, is a species of flowering plant in the family Violaceae, native to Eurasia and Africa. It is also called wood violet and dog violet. It inhabits woodland edges, grassland and shady hedge banks.  It is found in all soils except those which are acid or very wet.
Growing to 10 cm (3.9 in) tall and 50 cm (20 in) broad, this prostrate perennial has dark green, heart-shaped leaves and produces multiple violet coloured flowers in May and June.
Viola riviniana was voted the county flower of Lincolnshire in 2002, following a poll by the wild plant conservation charity Plantlife.


Common in  Ireland and all the British Isles.


It is the food plant of the pearl bordered fritillary, small pearl-bordered fritillary, silver-washed fritillary and high brown fritillary butterflies.
It is a known host of the pathogenic fungus Puccinia violae.


Viola odorata (sweet violet) – fragrant; all the leaves are located at the base of the plant; stipules are gland-tipped
Viola canina (heath dog violet) – clear blue flowers; narrower leaves; smaller teeth on the stipules
Viola palustris (marsh violet) – found in wet places; leaves are kidney-shaped; grows from underground creeping stems; dark-veined flowers; stipules without teeth
Viola labradorica (alpine violet) – V. riviniana is sometimes sold by nurseries as V. labradorica


This species hybridises with early dog-violet (V. reichenbachiana) to produce Viola × bavarica.


Viola sagittata, commonly called the arrowleaf violet, is a species of flowering plant in the violet family (Violaceae). It is native to the eastern North America in Canada and the United States, where it is widespread. It is found in a variety of natural habitats, but is most common in dry, open communities such as prairies, glades, or woodlands, often in sandy or rocky soil.
Viola sagittata is an stemless perennial. It can be distinguished from other Viola in its area by its leaves that are much longer than wide, with truncate to subcordate bases. It produces purple flowers in the spring.


Two varieties are currently recognized. They are quite distinct, which has led some taxonomists to consider them to be distinct species. The varieties are:
V. sagittata var. ovata - Found primarily in the Appalachian Mountains and Great Lakes area.
V. sagittata var. sagittata - Widespread across eastern North America.


Viola sempervirens, known by the common names redwood violet and evergreen violet, is a species in the genus Viola. It is native to the West Coast of the United States and British Columbia, Canada, and grows in closed-cone pine forest, California mixed evergreen forest, redwood forest, and Douglas fir forest communities.
It has leathery purple-spotted green leaves and bright yellow flowers. It blooms in winter and spring.


Viola sororia is a short-stemmed, herbaceous perennial plant that grows in well-drained and shady habitats. This 6-10 inch wide violet has glossy, heart-shaped leaves and are topped with purple flowers with white throats. The lower three petals are hairy and the  stem of the flower droops slightly. These flowers can be found in the woods, thickets, and near stream beds. This plant species can live and reproduce for over more than 10 years. Blooming in the Spring-Summer, or the months of April–August, Viola sororia can be found in colors of white, blue, or even purple.


Viola sororia are primarily found in forests and are interfertile, meaning they are likely and able to breed with other closely related species. The species grows on the forest floor and environment can adapt to sunny or partly shady conditions. The leaves on the Viola sororia develop in the early spring when the surrounding tree crowns are not fully closed. Still, when the canopy closes, the leaves continue to grow and develop. Soils preferred by V. sororia are moist, rich, and well drained.


Beyond its use as a common lawn and garden plant, Viola sororia has historically been used for food and for medicine. The flowers and leaves are edible, and some sources suggest the roots can also be eaten. The Cherokee used it to treat colds and headaches. Rafinesque, in his Medical Flora, a Manual of the Medical Botany of the United States of North America (1828–1830), wrote of Viola sororia being used by his American contemporaries for coughs, sore throats, and constipation.
The leaves are high in vitamins A and C and can be eaten raw. The flowers have been made into jelly and candy.
Viola sororia can also be used to decorate walkways and park areas. It is used as a wildflower in lawns, though some consider Viola sororia a weed, despite being a resource for pollinators. Viola sororia are also very high in vitamins A and C, which means they can be used in salads, cooked as greens, or even made into candies and jellies. The young leaves and flower buds can be eaten raw or cooked, or brewed for a tea. Viola sororia may also work as an anti-inflammatory and used topically for skin conditions.Viola sororia is deer resistant.


The caterpillars of fritillary butterflies feed on these plants. The plants also serve as food for wild turkeys, rabbits, deer, livestock, the mourning dove, the bobwhite, and the white-footed mouse.
Native bees such as the Mason Bees, Halictid Bees, and the most common, the Mining Bee, visit the Viola sororia plant for its nectar in the spring time. Butterflies are also known to pollinate from this species. These pollinated flowers result in a normal seed distribution like most flowering plants; however, Viola sororia produce seeds in the late summer from a process called cleistogamy. This means that it self-fertilizes inside the plant, without opening. The seed capsules eventually turn upright, opens, and shoots out their seeds as far as 9 feet away from the plant.
Violets employ myrmecochory, which is the process of the seeds being dispersed by ants. The seeds are coated with protein- and lipid-rich morsels, also known as elaiosomes, and they attract ants. The ants then gather the seeds and bring them back to their nests. When the coating is consumed by the ants, it is discarded into their waste piles, which is actually just planting the seeds. Although they have no known toxicities, when it comes to fire ecology, they are not fire resistant, and their fire tolerance is low. They have no serious insect or disease problems and their foliage usually declines in hot summers. Myrmecochory, is a form of mutualism between the Viola sororia plant species and a certain ant species. The diaspores have elaiosomes that attract ants and lead to the dispersal of the diaspores. The appendages are nutrient-rich, which induces some ant species to carry the diaspores from the plant, back to their nest. The elaiosome is consumed and the germinable seed is discarded. Ants can increase the dispersal distance by moving diaspore away from the parent plant, move them from other competitors and predators, and relocate them to favorable sites for germination. Within the ant nest, seeds may be protected from fire and seed predators, which is beneficial for the Viola sororia plant, considering they are not fire resistant.


Viola sororia leaves and flowers are edible in moderation and also safe to plant around pets.


Viola sororia is known as a wild violet that may be hard to control due to its sometime weedy nature. Halauxifen-methyl, has shown promising results on hard-to-control weeds, including Viola sororia.


It is the state flower of Illinois, Rhode Island, New Jersey, and Wisconsin. The genus, Viola, is known as a symbol of love and modesty by poets from Sappho to Shakespeare to Christina Rossetti. In the 1930s, a Broadway play featured a lesbian character that won over the lady she was in love with, with violets. This inspired a violet fad and was the reason why violets may also be known as "the lesbian flower".


Virbia laeta, the joyful holomelina, is a moth in the family Erebidae. It was described by Félix Édouard Guérin-Méneville in 1844. It is found in North America from New Brunswick south to Florida and west to Minnesota and south to Texas. The habitat consists of pine woodlands.
The length of the forewings is about 11 mm for males and 17 mm for females. The forewings are fuscous to dark greyish brown with a light salmon band. The hindwings are geranium pink. In Louisiana, adults have been recorded on wing year round (except December). In Texas, there are two generations per year with adults on wing in March and June. In the northern parts of the range, there seems to be one generation per year, with adults on wing in June and July.
Larvae have been reared on dandelion and plantain species.


The yellow-throated vireo (Vireo flavifrons) is a small American songbird.


"Vireo" is a Latin word referring to a green migratory bird, perhaps the female golden oriole, possibly the European greenfinch. The specific flavifrons is from the Latin words flavus, "yellow", and frons, "forehead".


The yellow-green vireo (Vireo flavoviridis) is a small American passerine bird. It is migratory breeding from Mexico to Panama and wintering in the northern and eastern Andes and the western Amazon Basin.


The yellow-green vireo was formally described by the American ornithologist John Cassin in 1851 under the binomial name Vireosylvia flavoviridis. The specific epithet combines the Latin flavus meaning "yellow" and viridis meaning "green". The type locality is San Juan de Nicaragua. The yellow-green vireo is now placed in the genus Vireo that was introduced in 1808 by the French ornithologist Louis Jean Pierre Vieillot.
Five subspecies are recognised:
V. f. hypoleucus Van Rossem & Hachisuka, 1937 – northwest Mexico (southeast Sonora to south Sinaloa)
V. f. flavoviridis (Cassin, 1851) – north central, northeast Mexico to Panama
V. f. forreri Madarász, 1885 – Islas Marías (off west Mexico)
V. f. perplexus (Phillips, AR, 1991) – north Guatemala
V. f. vanrossemi (Phillips, AR, 1991) – southeast El Salvador


The adult yellow-green vireo is 14–14.7 cm in length and weighs 18.5 g. It has olive-green upperparts and a dusky-edged gray crown. There is a dark line from the bill to the red-brown eyes, and a white supercilium. The underparts are white with yellow breast sides and flanks. Young birds are duller with brown eyes, a brown tint to the back, and less yellow on the underparts. The adult yellow-green vireo differs from the red-eyed vireo in its much yellower underparts, lack of a black border to the duller gray crown, yellower upperparts and different eye color.
Some individuals are difficult to separate, even in the hand, from the similar red-eyed vireo, with which it is sometimes considered conspecific. Its exact status as a passage bird in countries such as Venezuela is therefore uncertain.
The yellow-green vireo has a nasal nyaaah call, and the song is a repetitive veree veer viree, fee’er vireo viree, shorter and faster than that of the red-eyed vireo. This species rarely sings on its wintering grounds.


It breeds from southern Texas (occasionally the Rio Grande Valley) in the United States and the western and eastern mountain ranges of northern Mexico (the Sierra Madre Occidental and Sierra Madre Oriental—also the Cordillera Neovolcanica) south to central Panama. It is migratory, wintering in the northern and eastern Andes and the western Amazon basin. This vireo occurs in the canopy and middle levels of light woodland, the edges of forest, and gardens at altitudes from sea level to 1500 m.


Yellow-green vireos feed on  insects gleaned from tree foliage, favoring caterpillars and beetles. They also eat small fruits, including mistletoe berries, and, in winter quarters, those of Cymbopetalum mayanum (Annonaceae) and gumbo-limbo (Bursera simaruba).


The blue-headed vireo (Vireo solitarius) is a Neotropical migrating song bird found in North and Central America. There are currently two recognized subspecies that belong to the blue-headed vireo. It has a range that extends across Canada and the eastern coast of the United-States, Mexico and some of Central America. It prefers large temperate forests with a mix of evergreen trees and deciduous under growth.
As the name suggests, the blue-headed vireo is characterized by its blue-grey head and bold yellow wing bars. Both sexes are very similar in plumage and size. Juveniles also have a similar plumage.
Populations of the blue-headed vireo have been steadily increasing since the 1970s and were therefore classified as a "Least Concern" species in 2004.


The blue-headed vireo has similar plumage year round and does not drastically change its appearance during the breeding season. It can be characterized by its olive green upper body, two bold yellow wing bars down the edge of its wing, and a deep blue-grey crown from which it gets its name. The juvenile plumage of immature blue-headed vireos is not distinct but very similar to the adult plumage. While this bird's appearance is similar to the closely related Cassin's vireo (Vireo cassinii), the Cassin's vireo can be differentiated by its lighter yellow patches, a smaller, thinner bill, and a brownish-grey crown. There is little to no sexual dimorphism between males and females as both are similar in plumage colouration and size.
Like most Vireos, the blue-headed vireo is a relatively small bird with a length of 126–148 mm (5.0–5.8 in). The wingspan is usually found to be around 200–240 mm (7.9–9.4 in) and their weight is typically 13–19 g (0.46–0.67 oz). There are some subtle differences between the V.s. solitarius and V.s. alticola subspecies. V.s. alticola, the larger of the two subspecies, has a darker back with a larger wing length of 76–83.5 mm (2.99–3.29 in) and a bill length of 11–12 mm (0.43–0.47 in). Conversely, V.s. solitarius is slightly smaller with a wing length of 69.2–77.8 mm (2.72–3.06 in), and a bill length of 8.9–11 mm (0.35–0.43 in).
The average lifespan of the blue-headed vireo in the wild has been measured to be approximately 7 years and 5 months.


The blue-headed vireo is placed in the genus Vireo, a group of small migrating passerine birds that are characterized by their usually dull greenish colouring, and a simple, monotonous song. Members of this group are usually characterized by the presence or absence of eye-rings, eye-strips, and wing bars. There is no sexual dimorphism between sexes in this group.
Though it had been previously classified as a separate species, the blue-headed vireo along with the plumbeous vireo (Vireo plumbeus) and the Cassin's Vireo (V. cassinii) were lumped in the 1950s into a single species, based on morphological data. This group of vireos was collectively known as the "Solitary Vireo" (Vireo solitarius). This taxonomy prevailed until 1997 when new molecular data showed that there were in fact three distinct species. The taxonomy reverted to that prior to the 1950s, and the blue-headed vireo was once again its own species.
There are two recognized subspecies of blue-headed vireo:
Vireo solitarius solitarius – (Wilson, A, 1810) – is the nominate species. It is slightly smaller and breeds across Canada to south Pennsylvania and New Jersey. It overwinters in north-central and southern Mexico.
Vireo solitarius alticola  – Brewster, 1886 – is slightly larger than the nominate species. It breeds mainly in the Appalachian Mountains to northern Georgia. It overwinters in the Gulf States after a short migration.


Native to North America, the blue-headed vireo enjoys a large breeding range that extends over an immense area of Canada and northern United States. The breeding range of V.s. solitarius extends from northeastern British Columbia across Alberta, Saskatchewan, Manitoba, Ontario and Quebec and down to southern Pennsylvania and New Jersey. V.s. alticola has a distinct breeding range that includes western Maryland and south, mainly in the Appalachian Mountains, to northern Georgia. At the end of the breeding season, the blue-headed vireo migrates south to its overwintering area. V.s. solitarius has the longest migration of the two subspecies and inhabits an overwintering area that includes eastern and southern Mexico to northern Central America. V.s. alticola migrates across a shorter distance to an area that extends from southeastern Virginia to Texas.
Blue-headed vireos prefer to breed in cool temperate forests, which in the southern part of its breeding range are found at higher elevations. Evergreen forests with spruce, fir, hemlock, and pine mixed with deciduous growth such as alder shrubs, willow shrubs, poplar, birch or maple trees are the habitat of choice. During the winter, blue-headed vireos inhabit mixed woods of pines and hardwoods. They are also found in coastal and flood plain swamps and low shrubby thickets.
Year round, even during the breeding season, population density is somewhat low and spread out. Overwintering population densities are usually found to be lower than in the breeding season. The density of the population ultimately depends on the type of forest being inhabited.
During migration, blue-headed vireos are often found to flock with groups of different sparrow species but rarely with members of its own species.


When blue-headed vireos arrive on their breeding grounds, typically in mid-April, many deciduous trees have yet to leaf out, leading them to nest in evergreen trees including hemlocks (Tsuga). Recently, however, many hemlocks in eastern USA have been killed by an invasive Asian insect, the Hemlock woolly adelgid (Adelges tsugae), leaving the vireos with fewer nesting options until spring leaf opening begins for deciduous trees.


The primary song of the blue-headed vireo is a simple, slow, monotonous tune that is often confused with the faster red-eyed vireo (Vireo olivaceus) song. The primary song is sung only by the males and usually only during the breeding season. The males become quite vocal during the breeding season, with the song frequency reaching its height prior to mating and then decreasing after copulation. Both sexes share a series of calls that are used in both defence of nests, interspecies competition, and communication between breeding pairs while foraging.
When foraging during the breeding season, mated pairs constantly communicate with each other using a series of high pitched chirping calls.


Blue-headed vireos are mainly insectivorous birds but are also known to eat fleshy berries and fruit. They are equipped with short, strong bills used for processing insect prey with a tough carapace such as beetles. Foraging usually occurs in the mid level of trees. A foraging blue-headed vireo will hop from branch to branch on the same or to an adjacent tree and will then fly towards its prey to capture it. Typical prey consist mostly of caterpillars, butterflies and moths but may also include tree bugs, stink bugs, beetles, bees, ants, flies, dragonflies, grasshoppers, crickets, spiders and, on some occasions, snails. Fruit feeding occurs primarily during migration and overwintering, especially when overwintering in more tropical regions where fruit is more abundant or if the insect populations are low. This large and varied diet is an example of an opportunistic feeding strategy, allowing the blue-headed vireo to be plastic in its ability to adapt to resource availability.


When arriving to the breeding ground in mid-April, male vireos will hold large, individual territories that can range from 1.5–6.6 hectares (3.7–16.3 acres). Females will choose a male to mate with depending on the male's ability to defend and control a large territory. While defending their territory from other males, the male vireos will sing a primary song to attract females. Undecided females can usually be seen flying along the edges of competing male territories; usually this will force the two males into direct conflict for the right to copulate with the female.
Once a female has approached a suitable mate, the male will perform a series of mating rituals. Typically, these rituals involve the male building a courtship nest for the female. The courtship nest is not a full nest but is most likely an attempt by the male to display his ability to gather resources. Once the pair is established, the courtship nest is abandoned. Mating does not occur for approximately 2 weeks after pair has been established. During this time, the male and the female will cooperatively build a breeding nest which is typically formed between forking mid-level branches of evergreen and deciduous trees and are composed of twigs and foliage. Breeding nests are not reused in following breeding seasons.
In one breeding season, a female will lay 3–5 eggs at a rate of 1 egg per day. Eggs are creamy white with brown or black spots and are 17–23.1 x 13.3–15.8 mm (0.055–0.075 in x 0.04–0.05 in). Eggs are incubated for approximately 14 days after being laid. Once hatched, infants are highly altricial, often having little to no downy feathers. Infants open their eyes during day 5 or 6 and will begin to fledge after 14 days for a total chick-rearing period of 28 days. Once the young are able to leave the nest, the parents will split the juveniles and separate. Juveniles are usually dependent on the parent to provide food for approximately 1 month after leaving the nest. If the nest is destroyed or a mating pair produces a failed brood, an attempt to re-nest may occur but this ultimately depends on when the brood fails. If the brood fails early on in the season, there is a higher chance that the pair will re-nest, if later, the pair will often separate and not attempt a second brood.
Blue-headed vireo's have an atypical breeding strategy when compared to other closely related species. Blue-headed vireo males will assist their mates with daytime incubation of eggs, nest construction, and feeding of the chicks. Also, unlike most bird species, female blue-headed vireos do not attempt any extra-pair copulations with other males. Likewise, males make no attempt to guard females from other males, making blue-headed vireos both socially and genetically monogamous birds.


The increase in male blue-headed vireo parental care is thought to be attributed to the levels of testosterone and prolactin found in the plasma of these birds during the mating season. Testosterone, a steroid hormone that is secreted by the testes, has been found to increase aggressive behaviour in male birds during the breeding season and that these males display less parental care if their testosterone levels are maintained. Conversely, prolactin is a peptide hormone that is regulated by the hypothalamus that has been found at higher levels in birds that do the majority of incubation. It was found that in the early breeding season, male blue-headed vireos have a low testosterone level and will maintain this low level at all stages of the season. This low level does not affect the Vireo's ability to compete with other males for territory however, as a high testosterone level has been found to not be necessary for territory establishment. Prolactin levels of the males were found to be high very early on in the breeding season and are maintained for the duration of the season. This high level of prolactin along with a low testosterone level, explains why male blue-headed vireos are so involved in the construction of the nest, daytime incubation, and feeding of the nestlings.


Blue-headed vireos have a low nesting success rate, with about 10–30% of hatchlings surviving. Common predators of the blue-headed vireo eggs and chicks include blue jays, crows, and squirrels.
Often, when a nest is attacked by a blue jay, the male and female will execute coordinated attacks on the approaching predator. This usually involves one partner swooping towards the blue jay while calling the mate who will then execute a second attack. Blue-headed vireos have also been known to nest close to nesting raptorial birds that do not prey on them. It is thought that they use the raptors as protection from squirrels that are, in turn, hunted by these bird of prey.
The largest contributor to the low nesting success rate of the blue-headed vireo is most likely the parasitic brown-headed cowbird (Molothrus ater). These birds will often lay their large eggs overtop the existing brood, causing the parents to feed the cowbird which will ultimately starve the infant Vireos.


Viscaria vulgaris, the sticky catchfly or clammy campion, is a flowering plant in the family Caryophyllaceae.
It is an upright perennial growing to 60 cm (24 in) in height. The leaves are lanceolate. The flowers, which are 20 mm across and bright rosy-pink, appear in long whorled spikes from May to August. It grows on cliffs and rocky places.
The Latin name Viscaria means "sticky", and refers to the stickiness of the stem just below the leaf joints. The English common names reference the same feature.
Viscaria vulgaris is also grown as an ornamental garden plant. In British horticultural literature it is often referred to by its synonym Lychnis viscaria. The cultivar 'Splendens Plena', a double-flowered form, has won the Royal Horticultural Society’s Award of Garden Merit.


Vitex agnus-castus, also called vitex,  chaste tree (or chastetree), chasteberry, Abraham's balm, lilac chastetree, or monk's pepper, is a native of the Mediterranean region. It is one of the few temperate-zone species of Vitex, which is on the whole a genus of tropical and sub-tropical flowering plants. Theophrastus mentioned the shrub several times, as agnos (άγνος) in Enquiry into Plants. It has been long believed to be an anaphrodisiac – leading to its name as chaste tree – but its effectiveness for such action remains unproven.
Vitex is a cross-pollinating plant, but its self-pollination has been recorded.


Vitex, its name in Pliny the Elder, is derived from the Latin vieo, meaning to weave or to tie up, a reference to the use of Vitex agnus-castus in basketry. Its macaronic specific name agnus-castus repeats "chaste" in both Greek and Latin; the small tree was considered to be sacred to the virginal goddess Hestia/Vesta. The most common names are "chaste tree'", "vitex", and "monk's pepper".


Vitex agnus-castus is widely cultivated in warm temperate and subtropical regions for its delicate-textured aromatic foliage and butterfly-attracting mid-summer spikes of lavender flowers opening in late summer in cooler climates. It grows to a height of 1–5 m (3–16 ft). It requires full sun though tolerating partial shade, along with well-drained soil. Under ideal conditions it is hardy to −23 °C (−9 °F) USDA Zone 6, and can be found as far north as the south shore of Long Island and Nantucket on the East Coast of North America and in the mild southwest of England. In colder zones, the plant tends to die back to the ground, but as it flowers on new wood, flowering is not affected on vigorous growth in the following season. This plant is a brackish water dweller, indicating that it tolerates salt. Cold and wet weather results in dieback and losses. The plant grows well on loamy neutral to alkaline soil.
In cultivation in the UK,  the form Vitex agnus-castus f. latifolia has gained the Royal Horticultural Society’s Award of Garden Merit.
The fruits from one single tree can be harvested for more than 15 years. This indicates that the tree cannot be integrated in a usual crop rotation system. It is suggested to sow dissimilar plants such as monocots as its subsequent crop so that it might be easier to control the monk's pepper plant, the dicot. Because the fruits of monk's pepper tend to fall constantly and uncontrollably, it is likely that the plant can germinate from seed. It is said that at a row spacing of 180 cm (71 in), the overall best yield per hectare can be achieved if the plant spacing is around 70 cm (28 in). Pruning back the branches in autumn has a positive influence on fruit yield while a re-pruning in spring can induce an increase of vegetative shoot and thus to fruit yield loss.


This plant can also be reproduced vegetatively. One possibility is to use 5–8 cm (2–3 in) long piece of the ripening wood with buds in July or August and another is to cut the ripe wood in November and then let it root in a coldframe. Also in vitro reproduction with spike of the shoots or node explants is possible.


The flowering and ripening processes do not happen simultaneously, enabling harvesting of both fresh fruits and seeds over a long span of time. The fruits tend to fall from the plant as they ripen, getting lost in the soil. Thus, there is no optimal fixed harvest time. Consequently, to avoid yield loss, unripe fruits need to be harvested. This early harvesting has no effect on quality. Overall it is said that harvesting the fruits by hand is the most convenient solution.


Thysanoptera, also known as thrips, can cause great damage to the growth and the generative development of Vitex agnus-castus. The insect feeds on chaste tree by sucking up the contents or puncturing them. Also Chaste tree is the only known host (especially in Israel) for Hyalesthus obsoletus. This cicada is the vector for black wood disease of grapevines. Hyalesthus obsoletus prefers V. agnus-castus  as a host to the grapevine. In this case chaste tree can be used as a biological control agent by planting it around vineyards to trap the Hyalesthus obsoletus.V. agnus-castus was found not only to be an appropriate food source for the adult vectors, but also a reservoir of Candidatus Phytoplasma solani (bacterial Phytoplasma species), the causal agent of the Black wood disease in grapevines.
The pathogen-caused leaf spot disease can almost defoliate V. agnus castus. Furthermore, root rot can occur when soils are kept too moist.


Flavonoids (vitexin, casticin), iridoid glycoside (agnuside, aucubin), p-hydroxybenzoic acid, alkaloids, essential oils, fatty oils, diterpenoids and steroids have been identified in the chemical analysis of Vitex agnus-castus. They occur in the fruits and in the leaves.


Essential oils have been found in the fruits and in the leaves. The oil of leaves, unripe and ripe fruits differ in compounds. 50 compounds were identified in the oil of unripe fruits, 51 compounds in the oil of ripe fruits and 46 compounds in the oil of the leaves. 1,8-cineole and sabinene are the main monoterpene components and beta-caryophyllene is the major sesquiterpene compound found in the fruits of Vitex agnus-castus. There are some slight differences between fruits from white flowering plants and such from violet flowering ones. The oil of fruits of white flowering plants have a higher amount of monoterpene constituents. The leaves mainly contain 1,8-cineole, trans-beta-farnesene, alpha-pinene, trans-beta-caryophyllene, and terpinen-4-ol. The oil, particularly from white flowering plants, is under preliminary research for its potential antibacterial effects.


The leaves and tender stem growth of the upper 10 cm (3.9 in), along with the flowers and ripening seeds, are harvested for alternative medicinal purposes. It is believed the berries are a tonic herb for both the male and female reproductive systems. The leaves are believed to have the same effect, but to a lesser degree. The leaves, flowers, and/or berries may be consumed as a decoction, traditional tincture, cider vinegar tincture, syrup, elixir, or simply eaten from the plant with presumed benefits as food. A popular way of taking Vitex is on awakening as a simple 1:1 fluid extract, which is said to interact with hormonal circadian rhythms most effectively.
In ancient times, it was believed to be an anaphrodisiac, hence the name chaste tree. Pliny, in his Historia Naturalis, reported the use of stems and leaves of this plant by women as bedding "to cool the heat of lust" during the time of the Thesmophoria, when Athenian women left their husbands to remain ritually chaste. At the end of the 14th century, John Trevisa reported of it "the herbe agnus-castus is always grene, and the flowre therof is namly callyd Agnus Castus, for wyth smel and vse it maketh men chaste as a lombe".  In the 15th-century poem The Flower and the Leaf, it is referred to as an attribute of the chaste Diana, and in the 16th century the English herbalist William Turner reported the same anaphrodisiac properties of the seed, both fried and not fried.


Vitex has been used in traditional medicine for reproductive health issues in women, but there is no high-quality clinical evidence for its effectiveness due to experimental design weaknesses.
Although vitex is commonly recommended in Germany, there are further indications that Vitex agnus-castus should be avoided during pregnancy due to the possibility of complications.


The most frequent adverse effects from vitex use include nausea, headache, gastrointestinal discomfort, menstrual discomfort, fatigue, and skin disorders. People taking dopamine-related medications or Parkinson's disease medications should avoid using chasteberry. Women on birth control pills, hormone replacement therapy, or having a hormone-sensitive condition, such as breast cancer, are advised not to use chasteberry. Use of vitex is discouraged for pregnant or breastfeeding women, and for children.


Vitex rotundifolia, the roundleaf chastetree or beach vitex, is a species of flowering plant in the sage family Lamiaceae. It is native to seashores throughout the Pacific. Its range includes continents and islands stretching from India east to Hawaii and from Korea south to Australia. This shrub typically grows approximately 1 m in height. It has a sprawling growth habit and produces runners that root regularly at nodes. This rooting pattern allows the plant to spread rapidly. At maturity, V. rotundifolia produces blue-purple flowers that are borne in clusters and ultimately yield small brown-black fruits. Its leaves are rounded at the tips with green upper surfaces and silver lower surfaces. While the plant is a seashore obligate, it grows over a wide latitude range. It has been used for medicinal purposes throughout its native range. More recently, it was imported to the eastern United States where it has become a seashore invasive. Control efforts are presently underway to protect the fragile beach dune ecosystem.


Vitex rotundifolia is a sprawling shrub that can grow as tall as 1.5 m though it typically ranges from 0.5 to 1 m in height. As a product of its rapid nodal rooting, the plant can form dense mats reaching in excess of 10 m from the parent plant.


New stems are green, square and fleshy initially before maturing brown and woody. Older, large-diameter stems are covered with heavily fissured bark. Running horizontal stems produce frequent upright branches. Leaves are strongly aromatic, intensifying when crushed.


The majority of leaves are simple, but they can occasionally be palmate trifoliate or 2-leaved. Leaves measure 2 to 6.5 cm in length and 1–4.5 cm in width. Leaf margins are entire. The leaf shape varies from ovate to obovate with acute bases and obtuse apices. Occasionally, leaf apexes are acute or emarginate. Upper leaf surfaces are dark green whereas lower leaf surfaces range in color from silver to white to light green; all leaf surfaces are tomentose. Petiole bases are typically somewhat purple and measure 0 to 1 cm in length. Blades are cupped downward slightly. Leaf veins are lighter green than surrounding tissue.


The flowers are borne in indeterminate panicles that may be terminal or axillary. Infloresences measure 3 to 7 cm in length. The calyx is cup-shaped and 4 to 4.5 cm long. Flowers are zygomorphic, purple to blue-purple, and short pedunculate. They are two-lipped and funnel-form (measuring 8 mm in length). Four stamens are didynamous and extend beyond the corolla tube (measuring 9 to 10 mm). The style extends beyond the stamens (total length: 12 mm). Pollen is tricolpate. Ovaries consist of two carpels with each containing two single seeded locules.


The fruits are globose drupes that are green while immature but turn yellow and red before maturing to bluish black. The fruits are frequently incorrectly characterized in the literature as "seeds or berries". Each drupe contains a maximum of four seeds though there are usually fewer as a result of seed abortion.


Each seed is encapsulated in a separate compartment. Endosperm is absent. Seeds germinate into tender seedlings that bear two cotyledons and quickly develop two red-margined true leaves. Ploidy level is 2n = 32, 34*.


Vitex rotundifolia is a member of the family Lamiaceae and subfamily Viticoideae. The plant was originally described by the son of Carl Linnaeus, Carl Linnaeus the Younger The original description was published in Supplementum Plantarum in 1782. The generic epithet, Vitex, is derived from the Latin viere, meaning “to bind or twist” in reference to the rope-like stems produced by some species in the genus. The specific epithet, rotundifolia, is derived from the Latin rotundus, which means "round, spherical", and folium, meaning "leaf.” This is a reference to the rounded character of the leaves.


Vitex and all other members of the family Verbenaceae save those in the subfamily Verbenoideae were recently moved to the family Lamiaceae. As a result of this reorganization, two monophyletic families were established from the paraphyletic Verbenaceae and polyphyletic Lamiaceae. This new classification scheme was initially proposed by Cantino in 1992. Subsequent cpDNA analysis, rbcL sequence analysis, chemotaxonomic studies, and morphological analyses  have supported the original logic for family reorganization.
This revision has resulted in some confusion regarding the classification of V. rotundifolia in the literature. Despite the fact that the revision is well supported with volumes of data, many authors continue to incorrectly place the plant in Verbenaceae.


Recent revisions of the genus Vitex have placed V. rotundifolia in synonymy with V. trifolia subsp. littoralis Steenis. Previous researchers have placed V. rotundifolia within V. trifolia. Moldenke (1958)  placed V. rotundifolia in synonymy with V. trifolia var. simplicifolia. The placement of Moldenke was in disagreement with Corner (1939), which held V. rotundifolia as distinct from V. trifolia. The placement of Corner was subsequently supported by several authors: Fosberg (1962), Munir (1987), and Wagner (1999).


Likely due to the wide range over which V. rotundifolia is native, the plant has acquired a host of common names.
English speaking countries
Beach vitex
Round-leaved chaste tree
Single-leaf chaste tree
Chasteberry
Monk's pepper
China
Dan ye man jing
Japan
Hamagou
Korea
Sunbiginamu
Man Hyung Ja(mainly medicinal name)
Hawaii
Kolokolo kahakai
Hinahina kolo
Manawanawa
Mawanawana
Pōhinahina
Polinalina


Multiple hybrids between Vitex agnus-castus and Vitex rotundifolia have been developed at the Chicago Botanic Garden. These cultivars have undergone successful trials at Longwood Gardens. The characteristics of the hybrids are more like those of V. rotundifolia than V. agnus-castus. However, the hybrids are more upright than V. rotundifolia and have been described as "open and spreading." The leaf characteristics are intermediate between the two parent plants while the blue-purple flower color of the parents persists in the hybrid.


V. rotundifolia grows along sandy and rocky coasts from 0 to 15 m above sea level. Plants grow down to the ocean waves themselves. V. rotundifolia is highly tolerant of the harsh beach dune environment characterized by intense heat, high wind, coarse-textured soil, and elevated salinity.
This plant's natural range includes much of the Pacific Rim and many of the Pacific islands. The plant was observed by Munir from Northern and Western Australia, New Guinea, Indonesia, New Caledonia, Polynesia, Hawaii, Malaya, Philippines, and Hong Kong. Moldenke reported V. rotundifolia in Brazil, Mauritius, Reunion, Bangladesh, Sri Lanka, Andaman Islands, China, Taiwan, Japan, Ryukyu Islands, Korea, Indochina, Thailand, Borneo, and Sarawak. The plant has also been observed in southern India. Cultivation of V. rotundifolia has been reported in England, Florida, Germany, the Hawaiian Islands, Hong Kong, Java, Johnston Island, Maryland, and New York. At present in the United States, beach vitex has become naturalized only in southeastern states along the east and gulf coasts.


Beach vitex is a perennial that grows throughout the summer months in temperate and tropical areas of the Pacific. In temperate areas, the plant is deciduous and loses its leaves during the cool nights of fall. In the southeastern United States, leaves emerge in April while flowering occurs from June–August with fruiting following shortly thereafter. Fruits may remain attached to the plant into the early spring. V. rotundifolia is capable of overwintering on the dunes in South and North Carolina and in gulf coastal areas. It can survive in USDA hardiness zones 6b to 10.


The plant grows rapidly, and reproduces through vegetative means. As the plant matures, it begins to flower. After maturation, the plant produces large numbers of fruits (up to 5581 fruits per square meter).


Insect visitation is the likely method of pollen transfer due to the spatial separation of the anthers and stigma, which would make self-pollination unlikely. Abe reported V. rotundifolia flowers on Nishino-shima Island were visited by flies, honey bees, beetles, butterflies, and ants though most of the visitors were ants. Diverse groups of pollinators visit the flowers in search of the 0.5 µl/flower nectar reward. Due to this wide range of visitors, it is unlikely the plant would require a specialist insect to mediate successful pollination.


Evidence indicates that beach vitex possesses a combinational dormancy mechanism. This dormancy mechanism is made up of a physical dormancy component and a physiological dormancy component. The physical dormancy mechanism is believed to be inforced at least in part by cuticular alkanes that prevent water penetration. The mechanism of the physiological dormancy component is not yet fully understood. This dormancy mechanism allows for the establishment of a substantial soil seed bank that is capable of surviving and producing new seedlings in excess of 4 years after all vegetation has been removed. Dormancy mechanisms also allow the plant to undergo long-distance dispersal.


There is substantial supportive evidence of a water-based dispersal mechanism for beach vitex fruits. V. rotundifolia plants are present throughout the Pacific including coastal areas of two continents and many islands. Bird dispersal is highly unlikely as there is no fleshy fruit reward; water dispersal is the most likely dispersal means capable of enabling dispersal over such long distances. Fruits are covered with thick coatings of hydrophobic cuticular alkanes allowing them to resist water penetration for extended periods.  Researchers have observed V. rotundifolia fruits floating on rivers and oceans.


Genetic diversity within populations has been found to be much lower than the average for most woody plants. Additionally, the divergence between populations was found to be higher. There were large genetic differences between populations, indicating there is limited gene flow between populations. This is understandable due to the limited ecological niche beach vitex inhabits. Since the populations are largely clonal, this may enhance genetic drift. Significant variations have been observed with regard to genotype and chemotype of various beach vitex samples collected from across China. Genotypic and chemotypic variations were closely associated. Large genetic variation between populations was observed with lower variation within populations, and plants within 20 m of each other were closely related. It was believed that differentiation of separated populations might be the cause of variations between populations.


Vitex rotundifolia has many medicinal uses. These uses generally parallel those of Vitex agnus-castus.