Sosnowsky’s hogweed

This article is about the species. For the invasive giant hogweeds in general, see Giant hogweed. For the genus, see Heracleum.

Sosnowsky’s hogweed (Heracleum sosnowskyi; Russian borshchevik Sosnovskogo) is a giant hogweed native to the Caucasus. From 1947 it was introduced into cultivation in the Soviet Union as a high-yielding silage crop, and in the 1960s its seed was sent to farms across the country.¹ The crop disappointed: its sap burned the people who handled it, and its smell got into the milk and meat of the animals that ate it.¹² Cultivation stopped in the 1980s, and in the 1990s, as collective agriculture collapsed and fields were abandoned, the plant spread out of control.¹³

It is now among the most troublesome invasive plants of Russia, the Baltic states, Belarus and Poland. The European Union lists it as an invasive alien species of Union concern.⁴ In Russia its registered variety was struck off the state register in 2012 for having lost its economic usefulness, and in 2015 the plant was officially reclassified from crop to weed.⁵ Rosselkhoznadzor, the Russian agricultural inspectorate, has called it a silage “miracle” that did not justify the trust placed in it.⁶it did not justify the trust placed in it

Taxonomy

The species was named in 1944 by the botanist Ida P. Mandenova, from material collected in Meskheti, Georgia.⁷¹ It honours the Caucasian botanist Dmitrii Ivanovich Sosnowsky, whose dates are given as 1885–1952 by some sources and 1886–1953 by others.⁷ Mandenova placed it with giant hogweed, H. mantegazzianum, in section Pubescentia of the genus.¹

It is smaller than giant hogweed, up to about 3 m tall, with less deeply divided leaves.⁸ In its native range it grows in the eastern and central Caucasus, from Dagestan and Kabardino-Balkaria through Georgia to northern Armenia and north-eastern Turkey.¹ Its genome, sequenced in 2023, contains 55,106 genes, far more than the 25,000–35,000 usual in plants.⁹

Whether the Soviet crop was Sosnowsky’s hogweed at all has been questioned. DNA barcodes of invasive plants from around Kirovsk and Syktyvkar, the two places where the introduction began, matched giant hogweed, H. mantegazzianum; the authors suggest the two species hybridised in the first trial plots.¹⁰¹¹ Giant hogweed was itself tried in the Soviet Union on a smaller scale.¹ If the identification holds, the Soviet fodder crop and the Victorian garden ornamental were the same species. See Heracleum § Names.

History

Introduction

The search for the plant began in what Russian historians of the episode call the hard post-war years, when the Soviet Union sought to restore and raise the productivity of its agriculture as quickly as possible.¹ The farm of the Polar-Alpine Botanical Garden at Kirovsk, on the Kola Peninsula, had been the first in Soviet practice to make silage from perennial herbs.¹ In 1946 A. A. Marchenko was assigned to compare such herbs, and Sosnowsky’s hogweed produced the most biomass.¹² In 1947 plants from near Nalchik, in Kabardino-Balkaria, were brought to the garden for trial as a silage crop.¹¹⁰

The work spread outwards. In 1951 or 1952 seed went to the Institute of Biology in Syktyvkar, in the Komi Republic, which became the all-Union centre for the introduction of new silage plants.¹¹⁰ Further centres followed near Leningrad, in Nalchik, where breeders tried to produce varieties that would not burn, at Lobnya near Moscow from 1959, and in the 1970s at the Timiryazev Agricultural Academy. In 1956 the plant was placed on the list for pilot-scale trials.¹

Historians of the introduction distinguish four stages: local trials from the late 1940s, mass introduction from the late 1950s, completion from the mid-1970s, and uncontrolled invasion from the 1990s.¹³

Mass planting

After Ozerova & Krivosheina (2018), Shadrin et al. (2023) and the Latvian Ministry of Environment (2007).

From the 1960s the plant was grown on a mass scale across the Soviet Union, although its sap was already known to burn skin.¹ From 1962 to 1966 alone, 5,500 kg of seed of the new silage plants, hogweed among them, were sent from Syktyvkar to nearly 1,500 farms.¹⁰ In Latvia the first production sowing was made in 1968 on the state farm Barkava, from half a kilogram of seed; the first field covered 0.2 ha, and by the end of the 1970s the farm grew 40 ha.¹⁴ The crop was also grown in the other Baltic republics, Ukraine, Belarus, Moldavia and Kyrgyzstan.¹

The total area will never be known: Soviet agricultural statistics recorded hogweed together with other silage crops.¹ Some of the spread followed the needs of research rather than of farms. In the Rzhev district of Kalinin Oblast, where 140 ha were planted and seed was sent to sixty addresses, historians connect the plant’s later spread into several oblasts with dissertation research based at the Timiryazev Academy.¹

Breeders tried to remove the burn. According to I. F. Satsyperova, whose collection at the Komarov Botanical Institute compared thirty species of Heracleum, breeding of Sosnowsky’s hogweed continued into the 1980s and came to nothing, because the production of photodynamic furanocoumarins is a dominant trait.¹ A variety, ‘Severyanin’, was nevertheless registered.⁵

Problems

The burns were known from the 1950s.¹ Early feeding trials found no harm to the animals, and cows fed the silage gave more milk.¹² Later work was less encouraging. In the early 1980s it was shown that furanocoumarins survive in silage and weaken the lactic fermentation that preserves it; the plant’s smell passed into meat and milk; and cows ate hogweed silage poorly when they had anything else.¹ In the Baltic states the anise taste of the milk and the danger to people and cattle led to the abandonment of the plantations.²

Abandonment and spread

Cultivation stopped in the 1980s, and research on the crop was wound down in the second half of the decade.¹³ Feral plants had been found near Moscow as early as 1948, and escapes were seen everywhere from the 1970s.¹

The great expansion came in the 1990s. With what Russian authors describe as the destruction of the agro-industrial complex, the spread went out of control and took on the character of an ecological disaster.¹ Agricultural enterprises collapsed, regular mowing stopped, and fields became waste ground, which the plant occupied, spreading along the roads.³ About twenty years passed between its spread into towns and villages and the first official control measures. It is recorded in 54 of Russia’s federal subjects, and since 2005 has been found outside farmland in Siberia.¹⁵sown by the plan, spread by its absence

Distribution

Sources: Dalke et al. (2018); Rosselkhoznadzor (2023, 2025); Lukicheva (2014); EPPO; Latvian State Plant Protection Service; Jodaugienė et al. (2018); Estonian Environmental Board; Ministry of Natural Resources of Belarus (2023).

Claims in the popular press of tens of millions of hectares¹⁶ are far above anything measured on the ground.¹⁵

Control and law

The public contracts for mapping and destroying the plant in Russia between 2011 and 2017 cost 314 million roubles; Leningrad, Moscow and Vologda oblasts accounted for nine-tenths of the area treated.¹⁵

Russia removed the plant from the national classifier of agricultural products from 1 January 2015, so that it lost the status of a crop, and added it to the industry classifier of weeds in the same year.⁵ It is not a quarantine pest.⁶ Since 1 March 2026 a federal law has obliged holders of land to destroy dangerous invasive plants on their land, on pain of losing it. The law defines such plants as those whose spread threatens the environment, human health and biodiversity, and causes harm to particular sectors of the economy; the lists are drawn up by each region.¹⁷ In Moscow Oblast, fines of up to a million roubles have applied since 2018. In 2025 the oblast replaced the fine for citizens with a fixed 5,000 roubles, finding the old range out of proportion to the cost of removing the plant.¹⁸¹⁹

In Latvia, where a 1986 paper had called the plant a “botanical raccoon dog”,¹⁴ a national programme for 2006–2012 was costed at 15.35 million lats.²⁰ Since 2008 owners of infested land have had to register it, submit a control plan, continue until the stand is gone, and monitor for at least five years. A flowering plant with a developed umbel counts as proof that control was not carried out.²¹ Estonia decided to eradicate the plant in 2003,²² and Lithuania has listed it for compulsory control since 2001.²³

The European Union placed Sosnowsky’s hogweed on its list of invasive alien species of Union concern in 2016; it may no longer be kept, grown, sold or released.⁴ The raccoon dog was added to the same list the following year.²⁴

In culture

In Polish and Russian-language journalism the plant is sometimes called “Stalin’s revenge”, after the decision of 1947; the origin of the nickname is undocumented.²⁵ The Polish artist Liliana Zeic exhibited a plant in a glass case under that title in 2017.²⁶ In Moscow, the Et Cetera Theatre’s 2019 production of Mykola Kulish’s play Blessed Island set its second act on an island overgrown with beautiful but poisonous hogweed.²⁵

See also

• Giant hogweed
• Heracleum
• Furanocoumarin
• Control of giant hogweed

Footnotes

1. Ozerova, N. A.; Krivosheina, M. G. (2018). “Patterns of secondary range formation for Heracleum sosnowskyi and H. mantegazzianum on the territory of Russia”. Russian Journal of Biological Invasions. 9 (2): 155–162. doi:10.1134/S2075111718020091. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵ ↩¹⁶ ↩¹⁷ ↩¹⁸ ↩¹⁹ ↩²⁰ ↩²¹ ↩²²

2. Nielsen, C.; Ravn, H. P.; Nentwig, W.; Wade, M., eds. (2005). The Giant Hogweed Best Practice Manual: Guidelines for the management and control of an invasive weed in Europe. Hørsholm: Forest & Landscape Denmark. ISBN 87-7903-209-5. ↩ ↩²

3. Luneva, N. N. (2014). “Borshchevik Sosnovskogo v Rossiiskoi Federatsii” [Heracleum sosnowskyi in the Russian Federation]. Zashchita i Karantin Rastenii. 2014 (3): 12–18. ↩ ↩² ↩³

4. Commission Implementing Regulation (EU) 2016/1141 of 13 July 2016 adopting a list of invasive alien species of Union concern. Official Journal of the European Union L 189: 4. ↩ ↩²

5. Luneva, N. N.; Konechnaya, G. Yu.; Smekalova, T. N.; Chukhina, I. G. (2018). “On status of Heracleum sosnowskyi Manden. on the territory of Russian Federation”. Vestnik Zashchity Rastenii. 3 (97): 10–15. doi:10.31993/2308-6459-2018-3(97)-10-15. ↩ ↩² ↩³

6. Rosselkhoznadzor (14 July 2023). “Borshchevik Sosnovskogo: kak borot’sya s neopravdavshim doveriya silosnym chudom”. Retrieved 26 September 2026. ↩ ↩²

7. International Plant Names Index. Heracleum sosnowskyi Manden., Zametki Sist. Geogr. Rast. 12: 17 (1944); author records for Mandenova and Sosnowsky. Retrieved 26 September 2026. ↩ ↩²

8. EPPO Global Database. “Heracleum sosnowskyi: datasheet”. Retrieved 26 September 2026. ↩

9. Schelkunov, M. I.; Shtratnikova, V. Yu.; Klepikova, A. V.; et al. (2024). “The genome of the toxic invasive species Heracleum sosnowskyi carries an increased number of genes despite absence of recent whole-genome duplications”. The Plant Journal. 117 (2): 449–463. doi:10.1111/tpj.16500. ↩

10. Shadrin, D.; Dalke, I.; Zakhozhiy, I.; Shilnikov, D.; Kozhin, M.; Chadin, I. (2023). “Heracleum sosnowskyi or Heracleum mantegazzianum? DNA-based identification of invasive hogweeds (Apiaceae) in two key regions of the species’ invasion history in the territory of the former Soviet Union”. Research Square (preprint). doi:10.21203/rs.3.rs-3296382/v1. ↩ ↩² ↩³ ↩⁴

11. Shadrin, D. M.; Dalke, I. V.; Zakhozhiy, I. G.; et al. (2024). “DNA barcode marker analysis of Heracleum sosnowskyi Manden. and Heracleum mantegazzianum Sommier & Levier (Apiaceae) from European Russia”. Russian Journal of Biological Invasions. 15 (3): 416–431. doi:10.1134/S2075111724700309. ↩

12. Osipova, E. S.; Gladkov, E. A.; Tereshonok, D. V. (2026). “Heracleum sosnowskyi Manden. in the context of sustainable development: an aggressive invasive species with potential for utilisation in the extraction of furanocoumarins and essential oils”. Journal of Xenobiotics. 16 (1): 6. doi:10.3390/jox16010006. ↩ ↩²

13. Krivosheina, M. G.; Ozerova, N. A. (2019). “Introduction of Sosnowsky’s hogweed as a cause of landscape transformation”. IOP Conference Series: Earth and Environmental Science. 350: 012013. doi:10.1088/1755-1315/350/1/012013. ↩

14. Latvian Ministry of Environment; Ministry of Agriculture; et al. (2007). Latvānis, tā izplatības ierobežošana. Informatīvs materiāls [Hogweed and restricting its spread]. Riga. ↩ ↩²

15. Dalke, I. V.; Chadin, I. F.; Zakhozhiy, I. G. (2018). “Control of Sosnowskyi’s hogweed (Heracleum sosnowskyi Manden.) invasion on the territory of the Russian Federation”. Russian Journal of Biological Invasions. 9 (4): 331–344. doi:10.1134/S2075111718040045. ↩ ↩² ↩³

16. Tkachenko, K. G. (30 September 2020). “Borshchevik Sosnovskogo: rastenie-terminator ili kul’tura budushchego”. Kommersant Nauka. 24. ↩

17. Federal Law of the Russian Federation of 31 July 2025 No. 294-FZ “On amendments to the Land Code of the Russian Federation and certain legislative acts of the Russian Federation”. Official publication. ↩

18. Law of Moscow Oblast of 27 August 2018 No. 139/2018-OZ. Summary: Garant.ru. Retrieved 26 September 2026. ↩

19. Garant.ru (15 May 2025). “Fiksirovanny shtraf za nalichie na uchastke borshchevika vveli v Podmoskov’e”. Retrieved 26 September 2026. ↩

20. Cabinet of Ministers of Latvia, Order No. 426 of 6 June 2006, “Par Latvāņu izplatības ierobežošanas programmu 2006.–2012. gadam”. Latvijas Vēstnesis 90. likumi.lv. ↩

21. Cabinet of Ministers of Latvia, Regulation No. 559 of 14 July 2008, “Invazīvās augu sugas – Sosnovska latvāņa – izplatības ierobežošanas noteikumi”. likumi.lv. ↩

22. Estonian Environmental Board. “Hogweeds”. Loodusveeb. Retrieved 26 September 2026. ↩

23. Jodaugienė, D.; Marcinkevičienė, A.; Sinkevičienė, A. (2018). “Control of Heracleum sosnowskyi in Lithuania”. Julius-Kühn-Archiv. 458: 275–280. doi:10.5073/jka.2018.458.039. ↩

24. Commission Implementing Regulation (EU) 2017/1263 of 12 July 2017 updating the list of invasive alien species of Union concern. Official Journal of the European Union L 182: 37. ↩

25. Posner, L. (12 August 2020). “Can creativity kill the toxic plant known as Stalin’s Revenge?”. The Calvert Journal. Archived from the original. ↩ ↩²

26. Zeic, L. (2017). Stalin’s Revenge. Artist’s page, archived. ↩