Abstrakt
The distribution of Autumn hawkweed Hieracium sabaudum in the Czech Republic is examined, based on specimens held by 28 public herbaria. This species, classified within Hieracium sect.
Foliosa, is one of 58 native hawkweeds within the Czech flora. In total 2793 herbarium specimens of H. sabaudum collected in the country were revised, of which 1668 (i.e. approx. 71%) were originally identified correctly (including taxonomic synonyms).
Based on the number of specimens revised and data from botanical databases, the distribution map presented here may be considered representative. Hieracium sabaudum occurs in most parts of the country, although it is rare in mountain areas, or absent from them.
In the Czech National Phytosociological Database, its occurrence is recorded over a broad scale of various plant communities, most frequently in oak-hornbeam, thermophilous oak and pine forests and their fringes, in scrub, heath and in various types of secondary habitats such as quarries and roadsides. Using flow cytometry measurements and chromosome counts, ten plants originating from five populations were shown to be triploid (2n ~ 3x) and one plant was 2n = 27.