Browsing Intensity and Woody Species Selectivity of Wild Ungulates in a Forest Habitat, Hungary

Ungulate-vegetation interactions play a central role in shaping forest structure, regeneration, and biodiversity. This study quantified browsing intensity and woody species selectivity of wild ungulates in Valkó Forest, a mixed oak dominated habitat located near to Gödöllő, Hungary. With vegetation locations spaced 10 meters apart, two perpendicular transects were created, producing 261 sampling points. Four height classes (0–50, 50–100, 100–150, and 150–200 cm) reflecting the functional browsing zone of local ungulate species were recorded at each location using a 50 × 50 × 30 cm quadrat. Data were collected using KoboCollect and processed through Kobotoolbox for cleaning and analysis. Browsing intensity calculated as the proportion of browsed to available shoots revealed strong species‑specific selectivity. Acer spp., Tilia spp., and Carpinus spp. experienced the highest browsing pressure, frequently exceeding 40–60% shoot removal, indicating high palatability and accessibility. In contrast, structurally defended taxa such as Crataegus spp., Rosa spp., and Rubus spp. showed consistently low browsing despite being present in the understory. Plant part utilization patterns showed a dominance of leaf and shoot browsing, with combined leaf and stem removal in Acer spp., Carpinus spp., and Pyrus spp., suggesting these species provide tender, high‑biomass forage. Seasonal patterns were evident: early season browsing concentrated on soft shoots, while late‑season browsing shifted toward species retaining green biomass longer. Jacobs’ Index confirmed positive selection for Acer spp. (J = 0.31) and strong avoidance of Pyrus, Rubus, and Prunus spp. (J = –1). Shannon diversity metrics indicated that although the forest offers moderate browse diversity, ungulate consumption is less diverse and strongly focused on a narrow subset of palatable species. Overall, the findings show that plant species identity, shoot availability, and morphological characteristics like leaf size, shoot tenderness, and lack of thorns influence browsing behaviours in Valkó Forest.