Garlic mustard (
Alliaria petiolata) is a biennial
flowering plantThe flowering plants or angiosperms are the most diverse group of land plants. The flowering plants and the gymnosperms are the only extant groups of seed plants...
in the Mustard family,
BrassicaceaeBrassicaceae or Cruciferae, also known as the crucifers, the mustard family or cabbage family is a family of flowering plants . The name Brassicaceae is derived from the included genus Brassica. Cruciferae is an older name, meaning "cross-bearing", because the four petals of their flowers are...
. It is native to
EuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural River, the Caspian Sea, the Caucasus Mountains , and the Black Sea to the southeast...
, western and central
AsiaAsia is the world's largest and most populous continent, located in the eastern and northern hemispheres. It covers 8.6% of the earth's total surface area and with approximately 4 billion people, it hosts 60% of the world's current human population.Asia is traditionally defined as part of the...
, and northwestern
AfricaAfrica is the world's second-largest and second most-populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area. With a billion people in 61 territories, it accounts for about 14.8% of the...
, from
MoroccoMorocco, officially the Kingdom of Morocco, is a country located in North Africa with a population of nearly 32 million and an area just under . Its capital is Rabat, and its largest city is Casablanca. Morocco has a coast on the Atlantic Ocean that reaches past the Strait of Gibraltar into the...
,
IberiaThe Iberian Peninsula, or Iberia, is located in the extreme southwest of Europe and includes modern-day Spain, Portugal, Andorra and Gibraltar and a very small area of France. It is the westernmost of the three major southern European peninsulas—the Iberian, Italian, and Balkan peninsulas...
and the
British IslesThe British Isles are a group of islands off the northwest coast of continental Europe that include Great Britain, Ireland and numerous smaller islands. There are two sovereign states located on the islands: the United Kingdom of Great Britain and Northern Ireland, and Ireland...
, north to northern
ScandinaviaScandinavia is a geographical region in northern Europe that includes, and is named after, the Scanian Province. It consists of the kingdoms of Norway, Sweden, and Denmark...
, and east to northern
IndiaIndia, officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the south, the Arabian Sea on the west, and the Bay of Bengal...
and western
ChinaChina is a cultural region, an ancient civilization, and, depending on perspective, a national or multinational entity extending over a large area in East Asia....
(
XinjiangXinjiang is an autonomous region of the People's Republic of China and also claimed by the territory of the Republic of China.-Names:Older English-language reference works often refer to the area as Chinese Turkestan, Sinkiang, East...
). In the first year of growth, plants form attractive clumps of round shaped, slightly wrinkled leaves, that when crushed smell like garlic. The next year plants flower in spring, producing cross shaped white flowers in dense clusters, as the flowering stems bloom they elongate into a spike-like shape.
Garlic mustard (
Alliaria petiolata) is a biennial
flowering plantThe flowering plants or angiosperms are the most diverse group of land plants. The flowering plants and the gymnosperms are the only extant groups of seed plants...
in the Mustard family,
BrassicaceaeBrassicaceae or Cruciferae, also known as the crucifers, the mustard family or cabbage family is a family of flowering plants . The name Brassicaceae is derived from the included genus Brassica. Cruciferae is an older name, meaning "cross-bearing", because the four petals of their flowers are...
. It is native to
EuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural River, the Caspian Sea, the Caucasus Mountains , and the Black Sea to the southeast...
, western and central
AsiaAsia is the world's largest and most populous continent, located in the eastern and northern hemispheres. It covers 8.6% of the earth's total surface area and with approximately 4 billion people, it hosts 60% of the world's current human population.Asia is traditionally defined as part of the...
, and northwestern
AfricaAfrica is the world's second-largest and second most-populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area. With a billion people in 61 territories, it accounts for about 14.8% of the...
, from
MoroccoMorocco, officially the Kingdom of Morocco, is a country located in North Africa with a population of nearly 32 million and an area just under . Its capital is Rabat, and its largest city is Casablanca. Morocco has a coast on the Atlantic Ocean that reaches past the Strait of Gibraltar into the...
,
IberiaThe Iberian Peninsula, or Iberia, is located in the extreme southwest of Europe and includes modern-day Spain, Portugal, Andorra and Gibraltar and a very small area of France. It is the westernmost of the three major southern European peninsulas—the Iberian, Italian, and Balkan peninsulas...
and the
British IslesThe British Isles are a group of islands off the northwest coast of continental Europe that include Great Britain, Ireland and numerous smaller islands. There are two sovereign states located on the islands: the United Kingdom of Great Britain and Northern Ireland, and Ireland...
, north to northern
ScandinaviaScandinavia is a geographical region in northern Europe that includes, and is named after, the Scanian Province. It consists of the kingdoms of Norway, Sweden, and Denmark...
, and east to northern
IndiaIndia, officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the south, the Arabian Sea on the west, and the Bay of Bengal...
and western
ChinaChina is a cultural region, an ancient civilization, and, depending on perspective, a national or multinational entity extending over a large area in East Asia....
(
XinjiangXinjiang is an autonomous region of the People's Republic of China and also claimed by the territory of the Republic of China.-Names:Older English-language reference works often refer to the area as Chinese Turkestan, Sinkiang, East...
). In the first year of growth, plants form attractive clumps of round shaped, slightly wrinkled leaves, that when crushed smell like garlic. The next year plants flower in spring, producing cross shaped white flowers in dense clusters, as the flowering stems bloom they elongate into a spike-like shape. When blooming is complete, plants produce upright fruits that release seeds in mid summer. Plants are often found growing along the margins of hedgerows, giving rise to the old
BritishThe United Kingdom of Great Britain and Northern Ireland is a sovereign state located off the northwestern coast of continental Europe. It is an island country, spanning an archipelago including Great Britain, the northeastern part of Ireland, and many small islands...
folk name of
Jack-by-the-hedge. Other common names include
Garlic Root,
Hedge Garlic,
Sauce-alone,
Jack-in-the-bush,
Penny Hedge and
Poor Man's Mustard. The genus name
Alliaria, "resembling
AlliumAllium is the onion genus, with about 1,250 species, making it one of the largest plant genera in the world. Allium is classified in family Alliaceae although some botanical authorities have included it in the lily family ....
", refers to the
garlicAllium sativum, commonly known as garlic, is a species in the onion family Alliaceae. Its close relatives include the onion, shallot, leek, and chive. Garlic has been used throughout recorded history for both culinary and medicinal purposes. It has a characteristic pungent, spicy flavor that...
-like odour of the crushed foliage.
Description
It is a
herbaceousA herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level. They have no persistent woody stem above ground...
biennial plantA biennial plant is a flowering plant that takes two years to complete its biological lifecycle. In the first year the plant grows leaves, stems, and roots , then it enters a period of dormancy over the colder months. Usually the stem remains very short and the leaves are low to the ground, forming...
(sometimes an
annual plantAn annual plant is a plant that usually germinates, flowers, and dies in a year or season. True annuals will only live longer than a year if they are prevented from setting seed...
) growing from a deeply growing, thin, white taproot that is scented like a horse-radish. Plants grow from 30-100 cm (rarely to 130 cm) tall. The
leavesIn botany, a leaf is an above-ground plant organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin. There is continued debate about whether the flatness of leaves evolved to expose the chloroplasts to more light or to increase the absorption of carbon dioxide. In...
are stalked, triangular to heart-shaped, 10-15 cm long (of which about half being the
petioleIn botany, the petiole is the small stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly...
) and 2-6 cm broad, with a coarsely toothed margin. In biennial specimens, first-year plants appear as a rosette of green leaves close to the ground; these rosettes remain green through the winter and develop into mature flowering plants the following spring. The
flowerA flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to mediate the union of male sperm with female ovum in order to produce seeds...
s are produced in spring and summer in button-like clusters. Each small flower has four white petals 4-8 mm long and 2-3 mm broad, arranged in a cross shape. The
fruitThe term fruit has different meanings dependent on context, and the term is not synonymous in food preparation and biology. Fruits are the means by which flowering plants disseminate seeds, and the presence of seeds indicates that a structure is most likely a fruit, though not all seeds come from...
is an erect, slender, four-sided pod 4 to 5.5 cm long , called a
siliqueA silique is a fruit of 2 fused carpels that separate when ripe, leaving a persistent partition, with the length being more than twice the width. This classification includes many members of the Brassicaceae family, but some members, such as Capsella bursa-pastroris L., have a shorter fruit of...
, green maturing pale grey-brown, containing two rows of small shiny black
seedA seed , referred to as a kernel in some plants, is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s which are released when the pod splits open. Some plants can flower and complete their life-cycle in the first year. A single plant can produce hundreds of seeds, which scatter as much as several meters from the parent plant. Depending upon conditions, garlic mustard flowers either self-fertilize or are cross-pollinated by a variety of insects. Self-fertilized seeds are genetically identical to the parent plant, enhancing its ability to colonize an area where that genotype is suited to thrive.
Cultivation and uses
The leaves, flowers and fruit are edible as
foodFood is any substance, usually composed of carbohydrates, fats, proteins and water, that can be eaten or drunk by an animal, including humans, for nutrition or pleasure. Items considered food may be sourced from plants, animals or other categories such as fungus or fermented products like alcohol...
for
humanHumans are bipedal primates belonging to the species Homo sapiens in Hominidae, the great ape family. They are the only surviving member of the genus Homo. Humans have a highly developed brain, capable of abstract reasoning, language, introspection, and problem solving...
s, and are best when young. They have a mild flavour of both garlic and mustard, and are used in
saladSalad is any of a wide variety of dishes including: green salads; vegetable salads; salads of pasta, legumes, or grains; mixed salads incorporating meat, poultry, or seafood; and fruit salads. They include a mixture of cold or hot foods, often including raw vegetables and/or fruits.Green salads...
s and
pestoPesto is a sauce originating in Genoa in the Liguria region of northern Italy . The name is the contracted past participle of pestâ , in reference to the sauce's crushed herbs and garlic.-History:The ancient Romans ate a cheese spread called moretum which may sometimes...
. They were once used as medicine.
In Europe as many as 69 species of
insectInsects are arthropods, having a hard exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae. They are the most diverse group of animals on the planet and include more than a million species that are already described. Insects represent more than half of all...
s and 7 species of fungi utilize Garlic Mustard as a food plant, including the
larvaA larva is a young form of animal with indirect development, going through or undergoing metamorphosis ....
e of some
LepidopteraLepidoptera is an order of insects that includes moths and butterflies. It is one of the most speciose orders in the class Insecta, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...
species such as the
Garden CarpetThe Garden Carpet is a moth of the family Geometridae. It is an abundant and familiar species across its huge range which covers the whole Palearctic region, the Near East and North Africa....
moth.
As an invasive species
Garlic mustard was introduced in
North AmericaNorth America is the northern continent of the Americas, situated in the Earth's northern hemisphere and in the western hemisphere. It is bordered on the north by the Arctic Ocean, on the east by the North Atlantic Ocean, on the southeast by the Caribbean Sea, and on the west by the North Pacific...
as a culinary herb in the 1860s and is an
invasive species'Invasive species' is a phrase with several definitions. The first definition expresses the phrase in terms of non-indigenous species that adversely affect the habitats they invade economically, environmentally or ecologically...
in much of North America and is listed as a noxious or restricted plant as of 2006 in the US states of Alabama, Connecticut, Massachusetts, Minnesota, New Hampshire, Oregon, Vermont and Washington. Like most invasive plants, once it has an introduction into a new location, it persists and spreads into undisturbed plant communities. In many areas of its introduction in Eastern North America, it has become the dominant under-story species in woodland and flood plain environments, where eradication is difficult.
The insects and fungi that feed on it in its native habitat are not present in North America, increasing its seed productivity and allowing it to out-compete native plants. It is a possible threat to the West Virginia White Butterfly (
Pieris virginiensis) and Mustard White Butterfly (
Pieris oleracea); adult butterflies of both species lay their eggs on native
Dentaria or Toothwort plants, but they often confuse garlic mustard plants with
Dentaria and lay their eggs on garlic mustard, because they have similar flowers. The eggs and young butterflies cannot live on the garlic mustard, because it has chemicals that are toxic to the larvae and eggs.
A study published in 2006 concluded that Garlic Mustard produces
allelochemicalsAllelopathy is a biological phenomenon that is characteristic of some plants, algae, bacteria, coral and fungi by which they produce certain biochemicals that influence the growth and development of other organisms. The biochemicals, called allelochemicals can have a beneficial or detrimental...
that harm mycorrhizal fungi that many North American plants, including native forest trees, require for optimum growth. Additionally, because
White-tailed DeerThe white-tailed deer , also known as the Virginia deer, or simply as the whitetail, is a medium-sized deer native to the United States , Canada, Mexico, Central America, and in South America as far south as Peru...
rarely feed on Garlic Mustard, large deer populations may help to increase its population densities by consuming competing native plants. Trampling by browsing deer encourages additional seed growth by disturbing the soil. A complication to the eradication of Garlic Mustard from an area is the longevity of viable seeds in the ground. Seeds contained in the soil can germinate up to five years after being produced.
Research published in 2007 shows that, in Northeast Forests, garlic mustard rosettes increased the rate of native leaf litter decomposition, increasing nutrient availability and possibly creating conditions favorable to garlic mustard's own spread.
External links