Restored xerothermic grassland
Down between the southwest hill and the hillside forest, a small ravine has developed. For many years, the ravine has been overgrown with black locust, displacing grassland species from here and creating, as a result, a dense young forest. Black locust is an alien, invasive species, very easily spreading, not only by seeds, but also by root suckers, so fighting it on xerothermic grasslands is very difficult. A few years ago, however, we managed to control its expansion at this site by removing the topsoil along with the black locust seeds and root suckers. The surface was then sowed with seeds of xerothermic plants collected on the neighbouring grassland, and in several places we placed "implants", i.e. small fragments of grassland with roots of grasses and a seed base. The grassland is slowly recovering and shows very good promise. Robinia pseudoacacia, commonly called Black locust, is a tree native to North America. It was brought to Europe in 1601 by John Robin. It is an alien species with modest habitat requirements, it has not many enemies among insects and therefore it is strong competition for native species.