Persian hogweed, giant hogweed, and Sosnowsky’s hogweed are dangerous invasive introduced species. Because of their rapid spread and proliferation and high growth, these species are endangering our natural biotic communities. Physical contact with the weed’s sap in conjunction with exposure to sunlight can lead to adverse health effects (skin redness, blisters, and even scars).
Work to control introduced species of hogweed has begun
The Environmental Board has announced that this year’s country-wide control of introduced species of hogweed has begun. Control work will last until August or if necessary, until September. The goal of control is to reduce the spread of harmful hogweed species and their effect on people and the natural environment in Estonia. Control will consist of spraying hogweed plants with herbicides, digging them up, and removal of inflorescences. Control will be carried out across Estonia, regardless of the intended purpose or ownership form of the land hosting the hogweed colonies. In 2017, control was carried out across more than 2350 hectares.
Hogweed control is being funded by the Environmental Investment Centre, under the project “Control of introduced species of hogweed 2017”.
Hogweed control has been carried out annually since 2005 according to the “Long-term control strategy based on data on the spread of introduced species of hogweed (Heracleum) 2005-2010”. This strategy is the basis of the “Management plan for introduced species of hogweed (Heracleum)”, which was approved by the Minister of the Environment on 11 February 2010 and was the basis in 2010 for a funding request to the European Regional Development Fund. The management plan (7.34 MB, PDF) provides an overview of the biology of the species, their range, and different control methods.
The Minister of the Environment approved the new management plan (2011-2015) (2.44 MB, PDF) on 1 February 2011. Like the previous management plan, it provides an overview of the biology of introduced species of hogweed, their range, different control methods, and results achieved thus far.
Hogweed control is work, which carries a high level of responsibility, while under no circumstances may new seeds be allowed to ripen and reach the soil, nullifying earlier control efforts. The goal is to exhaust the existing supply of seeds in the soil seed bank, where they can remain viable for many years, and to prevent the introduction of new seeds. To ensure that the control work is carried out properly, without contaminating surrounding plants and biotic communities, those carrying out the control work must follow work and safety instructions. (163.49 KB, PDF)
The Environmental Board invites landowners and local governments to contribute to hogweed control efforts, especially in the case of colonies whose control has not been ordered on the basis of a public procurement contract. If recommendations and basic principles of control are followed, then all else that is needed is determination, enterprise, and patience. The weakening of bigger colonies takes time – a significant reduction in the number of hogweed plants is seen only after a 4-5 year long control cycle.
If you have any questions related to introduced species of hogweed or wish to report the discovery of a colony, please contact one of the following specialists:
• Harjumaa and Järvamaa - Käthlin Rillo, Monika Laurits-Arro
• Hiiumaa - Rita Miller
• Läänemaa - Ilona Lepik
• Saaremaa - Maarja Nõmm
• Jõgevamaa and Tartumaa - Tarmo Niitla
• Põlvamaa, Valgamaa, Võrumaa and Viljandimaa - Jarmo Jaanus
• Pärnumaa and Raplamaa - Marite Kungla
• Ida-Virumaa and Lääne-Virumaa - Katrin Jürgens
• across Estonia - Eike Vunk
All Environmental Board employee e-mail addresses are in the following form: firstname.lastname@example.org. Special characters are replaced with their standard counterparts.
When reporting the discovery of a hogweed colony, please provide your contact information and as precisely as possible, the location of the colony and a description of the site.
More detailed information about the species and their control methods can be found in the brochures “Introduced species of hogweed: Sosnowsky’s hogweed and giant hogweed”, “Sosnowsky’s hogweed” and “Introduced species of hogweed and some similar local species”. (851.34 KB, PDF)
Hogweed. Photo: Martin Ott.