L. Lőkös szerk.: Studia Botanica Hungarica 26. 1995 (Budapest, 1995)

Penksza, Károly: Flora of the Őr-hegy (Gerecse Mts, Hungary)

Studia bot. hung. 26, pp. 37-48, 1995 FLORA OF THE ŐR-HEGY (GERECSE MTS, HUNGARY) K. PENKSZA Department of Botany and Plant Physiology, Agricultural University H-2103 Gödöllő, Hungary Floristic data, collected by the author since 1984 on the Őr-hegy, near Bajna, Gerecse Mts, Hungary, are presented. It covers 459 vascular plants and 22 moss species. The species list given here is supplemented with former data of other authors. Key words: floristics, check-list, Gerecse Mts, Hungary INTRODUCTION Due to the accelerated environmental changes there is an increasing demand for the detection of the changes in the flora and vegetation of certain areas. The questions if a species become extinct or not, and which species appear or disappear are of high importance. This paper, dealing with the flora of the Őrhegy, near Bajna, Gerecse Mts, presenting the results of 8 years of regular fieldwork, provides a basis for later comparative studies. The first detailed botanical survey of the Gerecse Mts was done by FEICHTINGER (1865), who reported 65 species occurring in the area of the Őr-hegy and Bajna. His monography on the Esztergom county (FEICHTINGER 1899) and further contributions to the flora of the Gerecse Mts (KERNER 1857, HILLEBRANDT 1858, FRANK 1870, GAYER 1916, REDL 1926, PAPP 1937) do not contain new data for the Őr-hegy. BOROS carried out detailed field-work in the area for more than 20 years. He consequently inspected all significant sights that seemed to be promising. He investigated the Őr-hegy twice (BOROS 1938, 1952). Some mosses, including the species of the cave of the hill, and several vascular plants were recorded by him. He also published new data for the Gerecse Mts (BOROS 1940, 1944) and gave the description of the vegetation (BOROS 1953). The Mercuriali-Tilietwn forests of the Gerecse Mts were investigated by KOMLÓDI (1958) and FEKETE and JÁRAI-KOMLÓDI (1962), the rocky grasslands by SEREGÉLYES (1974, 1986), the bush forests by TÖRÖK (1977), and TÖRÖK and PODANI (1982), the Orno-Quercetum and Quercetum petraeae-cerris associations by SZOLLÁT (1987) and the Querco-Carpinetum by SZÁRAZ (1981). SEREGÉLYES (1977) published floristic data as well. In addition to the description of