A catalogue of neophytes in Belgium
A website providing access to a manual of the alien plants in Belgium has been made open access, providing records of all the alien vascular plants ever recorded in Belgium (with emphasis on those recorded since 1950).
The data available is based on the inventory of alien plants in Belgium that was compiled on the basis of herbarium data for the period 1800-2005. So far 1969 taxa were recorded and for each of them, the following information is provided: scientific name, synonyms, family, mode of introduction (accidental/deliberate), date of the first collection, date of the most recent record, native geographic area, presence or absence of the species in the three main administrative units in Belgium, degree of naturalization and (main) pathway(s) of introduction.
These 1969 species belong to 139 families, Poaceae and Asteraceae representing more than a quarter of alien taxa in Belgium. The main pathway for plant introductions appears to be horticulture (garden escapes). Until the 1960s, wool importation was responsible for some accidental introductions while nowadays, accidental aliens are usually brought in with cereals and grains. Introductions from Europe and Temperate Asia are the most common. To a lesser extent, Africa (especially North Africa) and America (especially North America) are also important sources. At most, 20 % of the alien species naturalized, but both the numbers of introduced and naturalized species greatly increased in the past decades.
An invasive species in this catalogue has been defined as a naturalized taxa that penetrates and proliferates in (semi-) natural habitats, not necessarily causing damage. Some invasive species actually cause severe damage in various ways: impact on biodiversity (aliens out-competing natives, etc.), health (aliens causing hay fever, photodermatitis) and/or economy (aliens disturbing watercourses, etc.) and these are also identified on the website. Noxious agricultural weeds were not identified in this study.
On this website the Catalogue of alien plants in Belgium is kept up-to-date permanently. The main objective of the website is to enable Belgian otanists to identify any vascular plant recorded in Belgium (native as well as non-native). For that purpose dichotomous identification keys are provided. There is an entry for each non-native taxon and all are illustrated (original line drawings, herbarium scans, photographs). Information about its invasion history, degree of naturalization, chorology, ecology, etc. are provided, as well as identification aids.
The construction of the website is still in progress: a limited number of families and genera are online but many additional ones are in production. A blog has also been created to draw the attention to new and/or overlooked interesting aliens.
Verloove F (2006) Catalogue of neophytes in Belgium (1800-2005). Meise, National Botanic Garden of Belgium 89 p.; ill.; 21 cm. – (Scripta Botanica Belgica, vol. 39).