INVASIVE PLANT SPECIES IN SHUMENSKO PLATO NATURAL PARK (NORTHEASTERN BULGARIA).

An investigation of the invasive plants distributed on the territory of the Shumensko Plato Natural Park was carried out for the first time. As a result, 19 invasive plant species were identified. The described species originate in different parts of the world, mainly in North America. The number of affected habitats is 14. In most habitats Ailanthus altissima and Robinia pseudoacacia are invading. Both species also have the highest count: 24,680 individuals of Ailanthus altissima and 5,628 individuals of Robinia pseudoacacia. In terms of biological type, most species are shrubs and annual herbaceous plants. In terms of life forms, the largest group is the group of phanerophytes that includes 11 tree and shrub species. The majority of invasive plants (12 species) are propagated simultaneously in two ways: by seeds and vegetatively. The main reason for the wide spread of invasive plants in the Park is their introduction as decorative plants or forest crops. Another reason is the transportation of fruits or seeds by vehicles. The authors recommend immediate measures to control the numbers and spread of invasive species in order to complete eradicate them from the Park territory. It is necessary to monitor the affected habitats for several years in order to prevent the invasive species? reoccurrence.