The Main Invasive Alien Plants in the Protected Areas in Central Italy (Abruzzo)

Abstract

The main invasive alien plants in the protected areas of the Abruzzo region have been recently pointed out. The areas taken into account have been the ones of the National Park of Abruzzo, National Park of Gran Sasso and Monti della Laga, National Park of Maiella, and the Regional Park of Sirente-Velino. The main plants have been found in the basal areas (400-1000 mt.), in uncultivated fields and urban surroundings (road and path margins, dumps, etc.). The most wide spread are the following: Asteraceae: Aster squamatus (Sprengel) Hieron.(Neotropical). Conyza Less. (C. bonariensis (L.) Cronq., C. canadensis (L.) Cronq.), Helianthus tuberosus I,. (North America), Xanthium spinosum L. (South America), Artemisia verlotiorum Lamotte (East Asia), Senecio inaequidens DC. (South Africa); Amarantaceae (Amaranthus chlorostachys Willd., A. retroflexus L., A, deflexus L.). The most invasive plant is Senecio inaequidens DC. (Asteraceae) which can be found in different areas, from the uncultivated calcium-rich fields to dumps, in the dry pastures and degraded oak-woods. A very common plant is also Isatis tinctoria L. (Cruciferae), an invasive plant coming from the South-East of Asia. It is very widespread in the ex-cultivated fields as it was introduced as a dyeing plant in the XVI century. Robinia pseudoacacia L. (Leguminosae) (native from Carolina and Virginia) and Ailanthus altissima (Miller) Swingle, Simaroubaceae (originated of China and Molucche Isles) are the most common trees. Phytosociological studies have been carried out on Senecio inaequidens, Isatis tinctoria, Artemisia verlotiorum and Amaranthus species with the purpose of defining their quantitative and qualitative presence both in urban surroundings and in natural environments. In the protected areas taken into examination the presence of invasive alien plants is of low entity. In the last decades Senecio inaequidens has represented a potential danger since it spreads very quickly and replaces the native flora. Phenological studies of Senecio inaequidens have shown a long period of flowering and seeds production.