Combating invasive neophytes
Environment Agency asks for help again this year
Plant species that only arrived in Central Europe after the Middle Ages or were introduced are known as neophytes ("new plants"). Some of them reproduce unhindered. As a result, they displace the native natural vegetation and form pure populations. In our area, these include in particular giant hogweed (photo) and balsam balsam, which are therefore also known as invasive neophytes.
In the protected areas where natural plant communities or near-natural vegetation can still be found, these invasive neophytes, including the knotweed species, are combated on behalf of the Lower Nature Conservation Authority. Giant hogweed occupies a special position among the invasive plant species, as it not only leads to displacement effects in nature, but also endangers human health through its sap. Originally from the Caucasus, it was introduced to England in 1817 and has since spread throughout most of Europe.
In our region, it germinates in April to May, then develops as a rosette plant for a few years and only reaches its full size of up to four metres in height when it begins to flower. Several tens of thousands of seeds ripen on the large whitish flower umbels and colonise new locations through water, wind and soil movement. Its large, strongly incised leaves are unmistakable, with each partial leaf and each serration of the partial leaves ending in a very typical leaf tip. The sap and the plant itself exude an unmistakable, strongly noticeable, pungent-spicy odour when warm. Giant hogweed has a superior propagation strategy to native perennials and has no natural enemies to keep it in check. It quickly forms pure stands, displaces the native vegetation and can colonise new locations in a very short time. The sap of the giant hogweed contains furanocoumarins, which can cause severe skin burns when exposed to sunlight. This can particularly affect children at play.
Due to the risk to human health and the displacement of native vegetation, the city of Chemnitz has decided to combat giant hogweed throughout the city. The respective landowner is generally responsible for this. The respective landowner will then receive a request from the Environmental Agency to remove the giant hogweed professionally within a reasonable period of time. For this purpose, flower and seed heads as well as the turnip-like root must be disposed of in a neophyte container at the Weißer Weg recycling centre, while the leaves and stems can be left on site to dry out.
Citizens are called upon to report giant bear claw occurrences to the Lower Nature Conservation Authority by telephone on 0371 488-3602 or -3603, or by email to umweltamt.naturschutz(at)stadt-chemnitz.de, giving precise details of the location and number of plants. You can also use the public authority telephone number 115.