Aesculus hippocastanum L.
Hippocastanaceae – Horse-chestnut family
Conservation status. Endangered [EN B1ab(ii,iii)+2ab(ii,iii)]. BDA. Balkan endemic. Tertiary relic.
Morphology and biology. Tree, up to 25 m, with large root system. Leaves digitate, up to 25 cm long, 20 cm wide; leaflets 5–7, obovate, cuneate at base, irregularly crenate-serrate. Inflorescence a conical panicle, up to 30 cm long. Sepals 5, connate. Petals 5, free, ciliate, white, with pink to reddish spots. Fruit globose, 3–6 cm in diameter, spiny, opening by 3 valves. Seeds 2.5 × 3 cm, subglobose, brown, smooth and shiny. Fl. IV−VI, fr. VIII−IX. Insect and wind pollination. Reproduction by seeds.
Habitats and populations. Grows in deciduous mesophilous forests. Only one population known, with relatively high number of individuals and density, forming a distinctive mono-dominant association as well as mixed associations with Carpinus betulus and Sambucus nigra.
Distribution in Bulgaria. Balkan Range (eastern – Preslavski Balkan, in the valleys of Dervishka, Zurleva, Lazarska and Akandzha rivers); at 180–600 m alt.
General distribution. Balkan Peninsula (Albania, Bulgaria, Greece, R Macedonia).
Threats. Very restricted distribution; active touring activities and pollution in the localities; wood extraction and forest fires. During the past several years the populations have been strongly infected by Cameraria ochridella (Lepidoptera), which feeds on the leaves and causes exhaustion of the trees.
Conservation measures taken. Protected species by the Biodiversity Act. Part of the population is within Dervisha Managed Nature Reserve. The localities are within a site of the European ecological network Natura 2000 in Bulgaria.
Conservation measures needed. Strict respect of the protection regime in the reserve; study on the reproductive biology of Cameraria ochridella and implementation of appropriate measures of its control; extensive ex situ cultivation of the species throughout the country with genetic material from natural localities.
References. Chernyavski et al. 1959; Palamarev 1979; Kochev & Gorunova 1972; Marinov 1984.
Author: Lyuba Evstatieva