The total number of 1,492 species amazed scientists. It represents almost a third of all wild-growing species in the Czech Republic. This fact remains unchanged despite some species within the city being limited to small populations. Besides native plants, several species introduced from other areas are also found in the city. Humans have introduced these non-native species into urban environments, intentionally mainly as ornamental plants or unintentionally as weeds.
The maps describe the percentage proportion of different groups of plants in Brno: native species on the left, invasive species in the middle, and threatened species on the right. Source: Faculty of Science, Masaryk University Archive.
"Each of the plants found in the city has its own story. Some are witnesses of the vanished natural or seminatural landscape, while others utilized and occupied new habitats, such as gravel pits, sidewalks, or cracks in walls." explains Zdeňka Lososová, project leader and botanist from the Faculty of Science at Masaryk University in Brno.
Stránská skála with blooming Pulsatilla grandis, blue-flowering Veronica prostrata, and yellow-flowering shrubs of Chamaecytisus ratisbonensis. Photo: Zdeňka Lososová
Brno, sometimes nicknamed the Moravian Manchester, was a significant center of the textile industry in the past two centuries. "Some non-native plants witness the city's industrial history, as they were introduced to the courtyards of textile mills with cotton and wool imported from South America or Australia. Some of them naturalized in the city most disappeared rapidly, but others have persisted in the city for decades. "Lososová explains. An example of such a plant is Artemisia tournefortiana, which could be two meters tall. In summer, other non-native species occur in the city. Those introduced mainly from southern Europe survive on the heated sidewalks as they tolerate the hot summer temperatures better than our native species.
Asplenium scolopendrium in a well at Špilberk. Photo: Deana Láníková
During the detailed survey, botanists also found 255 threatened plants in Brno. Most of them occur in protected areas. An iconic threatened species of the city of Brno is Pulsatilla grandis, whose flowers were admired by numerous visitors in March each year in the protected area Kamenný vrch. Some endangered plants are able to grow in the built-up parts of the city. An example of these plants is a fern named Asplenium scolopendrium, which naturally grows on screes in shady forested valleys. In the city, it can be found in old abandoned wells, where it has sufficient air humidity.
Koniklec velkokvětý (Pulsatilla grandis) se vyskytuje na několika lokalitách v Brně. Největší počet rostlin každoročně rozkvétá na Kamenném vrchu. Foto: Lubomír Tichý
The study was conducted between 2011 and 2021, involving a team of 37 professional and amateur botanists, including students. They systematically mapped spontaneous plants in Brno and created a series of unique maps with a grid of mapping cells measuring 1.3 x 1.5 km.
Kapradina jelení jazyk celolistý (Asplenium scolopendrium) ve studni na Špilberku. Foto: Deana Láníková