''Heracleum sosnowskyi'', or Sosnowsky's hogweed, is a

monocarpic Monocarpic plants are those that flower and set seeds only once, and then die. The term is derived from Greek (''mono'', "single" + ''karpos'', "fruit" or "grain"), and was first used by Alphonse de Candolle. Other terms with the same meaning ar ...

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wid ...

herbaceous

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

in the carrot

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Apiaceae Apiaceae or Umbelliferae is a family of mostly aromatic flowering plants named after the type genus '' Apium'' and commonly known as the celery, carrot or parsley family, or simply as umbellifers. It is the 16th-largest family of flowering plan ...

. Its native range includes the central and eastern

Caucasus The Caucasus () or Caucasia (), is a region between the Black Sea and the Caspian Sea, mainly comprising Armenia, Azerbaijan, Georgia (country), Georgia, and parts of Southern Russia. The Caucasus Mountains, including the Greater Caucasus range ...

regions of

Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago ...

and extends into the southern Caucasus region called

Transcaucasia The South Caucasus, also known as Transcaucasia or the Transcaucasus, is a geographical region on the border of Eastern Europe and Western Asia, straddling the southern Caucasus Mountains. The South Caucasus roughly corresponds to modern Arme ...

. The native ranges of ''Heracleum sosnowskyi'' and ''

Heracleum mantegazzianum ''Heracleum mantegazzianum'', commonly known as giant hogweed, is a monocarpic perennial herbaceous plant in the carrot family Apiaceae. ''H. mantegazzianum'' is also known as cartwheel-flower, giant cow parsley, giant cow parsnip, or hogsb ...

'', a close relative, overlap in the Caucasus region. Sosnowsky's hogweed is now a common

weed A weed is a plant considered undesirable in a particular situation, "a plant in the wrong place", or a plant growing where it is not wanted.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. ...

in the Baltic States,

Belarus Belarus,, , ; alternatively and formerly known as Byelorussia (from Russian ). officially the Republic of Belarus,; rus, Республика Беларусь, Respublika Belarus. is a landlocked country in Eastern Europe. It is bordered by ...

Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eig ...

Ukraine Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian inv ...

, and

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populou ...

. Early botanists considered ''H. sosnowskyi'' to be a subspecies of ''H. mantegazzianum''. Sosnowski's hogweed was described as a separate species by Ida P. Mandenova in 1944. The species is named in honor of the Russian botanist Dmitrii Ivanovich Sosnowsky (1885–1952), who found the species in

Georgia Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to the ...

in 1936.

Description

left, 192px, ''Heracleum sosnowskyi'' Inflorescences ''Heracleum sosnowskyi'' is 3–5 m in height, with a straight, firm stem that can reach a diameter of 12 cm. The leaves are 50–60 cm long. The

root In vascular plants, the roots are the organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often below the su ...

is very firm, up to 30 cm diameter. The

inflorescence An inflorescence is a group or cluster of flowers arranged on a Plant stem, stem that is composed of a main branch or a complicated arrangement of branches. Morphology (biology), Morphologically, it is the modified part of the shoot of sperma ...

is a big

umbel In botany, an umbel is an inflorescence that consists of a number of short flower stalks (called pedicels) that spread from a common point, somewhat like umbrella ribs. The word was coined in botanical usage in the 1590s, from Latin ''umbella'' "p ...

found at the end of every stem. It blooms during July through September and produces thousands of

seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...

s. They are easily distributed by the wind, but especially by the water. Sosnowsky's hogweed is a

, that is, after a mature plant flowers and produces seed, the entire plant including the root will die.

Invasiveness status

In Europe, Sosnowsky's hogweed is included since 2016 in the list of Invasive Alien Species of Union concern (the Union list). This implies that this species cannot be imported, cultivated, transported, commercialized, planted, or intentionally released into the environment in the whole of the European Union.

Public health and safety

All parts of ''H. sosnowskyi'' contain phototoxic

furanocoumarin The furanocoumarins, or furocoumarins, are a class of organic chemical compounds produced by a variety of plants. Most of the plant species found to contain furanocoumarins belong to a handful of plant families. The families Apiaceae and Rutacea ...

s. It is dangerous for humans because even small drops of plant's juice cause skin

photosensitivity Photosensitivity is the amount to which an object reacts upon receiving photons, especially visible light. In medicine, the term is principally used for abnormal reactions of the skin, and two types are distinguished, photoallergy and phototoxicit ...

and

burn A burn is an injury to skin, or other tissues, caused by heat, cold, electricity, chemicals, friction, or ultraviolet radiation (like sunburn). Most burns are due to heat from hot liquids (called scalding), solids, or fire. Burns occur ma ...

s. The plant is less dangerous for animals that have thick hair to protect them from the sun.

Control measures

The plant was common only in the Caucasus area, until it started to be used as a

silage Silage () is a type of fodder made from green foliage crops which have been preserved by fermentation to the point of acidification. It can be fed to cattle, sheep and other such ruminants (cud-chewing animals). The fermentation and storage ...

plant in other parts of the

Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

. As a result, it quickly spread in many areas of Russia, Belarus, and Ukraine. It is now a highly

invasive plant An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species adv ...

in the Baltic States, Russia, Poland, and Belarus. Many river valleys and roadsides are occupied by large stands of this weed. It is difficult to eradicate because the seeds remain viable for many years and the roots are difficult to remove. Herbicides are widely used in a fight against it, but the plant can later resprout from the roots. The plant is also used as a shield-hedge along the roads, preventing farm animals from escaping and wild animals from getting in. The decision to use the plant for

was made in 1947, under Stalin's rule, so when the species later proved to be highly invasive and difficult to remove, people started to call it "Stalin's revenge".

References

External links