Zoöp Observations: Cotton ThistleZoöp Observations: Cotton Thistle

Some cotton thistles (Onopordum acanthium) have blossomed in the sandy dune vegetation along the driveway of the New Institute. Last year these silver-gray biennial plants were still quite modest in size. But now, in their second and final year of life, with their strong, candelabra-shaped branches they stand taller than a person. The cotton thistle, which originates from Central Europe and Central Asia, is uncommon in the Netherlands. With the exception of the dune system, cotton thistles are mainly found in the fluvial landscapes in the middle of the Netherlands and Limburg. Furthermore, the plant has a certain preference for stony railway embankments. The cotton thistles didn't reach the New Garden on their own: they were sown in the spring of 2022, although it cannot be completely ruled out that some of the present plants have germinated from the soil-stored natural seed archive. Because there were already a few cotton thistles in the “old” New Garden (2015-2021). Seeds of the cotton thistle remain viable for up to six years.

As an ornamental plant, the cotton thistle has also found its way into (large) gardens and parks. In some places in North America, South America and Australia “garden escapee” cotton thistles are considered to be invasive exotics. In Germany and France, the plant is called donkey thistle (Eselsdistel, Chardon aux ânes), which refers to the genus name Onopordum. That genus name is derived from the Greek words onos (donkey) and pordè (fart) – the Roman writer Pliny the Elder noted in his Naturalis historia that the plant causes flatulence in donkeys.