Changes in the Hieracium flora in the Nässjö area (Småland, S Sweden) during the 20th century(Skogs- och hagfibblor i nässjötrakten i åttio års perspektiv)

The Hieracium flora in an area of 1250 km(2) centred around the town of Nassjo, S Sweden, was investigated in 1924-30 and again in 2004. In all, 101 species of the sections Hieracium and Vulgaria were found, 89 in the 1920s and 85 in 2004, i.e. approximately the same number. However, the number of species per 5 by 5-km area has been strongly reduced, and the decline is even more pronounced for 1 by 1-km areas. This implies that Hieracium species have generally become much rarer If the sample from the 1920s is unbiased, species of sect. Hieracium have declined more than those of sect. Vulgaria. In the 1920s, the main Hieracium habitat was wooded meadows cut for hay after mid-summer; hawkweeds were a conspicuous and species-rich element of their vegetation. Today, almost all the former hay-meadows have changed into forest or manured grassland, and the hawkweeds are usually gone. Species of sect. Vulgaria are now mainly fond on roadsides (70% of all localities) whereas those of sect. Hieracium prefer woodland (63% of all localities). However, species of the Bifida group within sect. Hieracium have the same habitat preferences as sect. Vulgaria. - Two species are new to the province of Smaland, viz. H. constringens Norrl. and H. expallidiforme (Dahlst. ex Stenstr) Dahlst. Names in Swedish are provided.