Development and application of a second-generation multilingual tool for invasion risk screening of non-native terrestrial plants.

Under the increasing threat to native ecosystems posed by non-native species invasions, there is an urgent need for decision support tools that can more effectively identify non-native species likely to become invasive. As part of the screening (first step) component in non-native species risk analysis, decision support tools have been developed for aquatic and terrestrial organisms. Amongst these tools is the Weed Risk Assessment (WRA) for screening non-native plants. The WRA has provided the foundations for developing the first-generation WRA-type Invasiveness Screening Kit (ISK) tools applicable to a range of aquatic species, and more recently for the second-generation ISK tools applicable to all aquatic organisms (including plants) and terrestrial animals. Given the most extensive usage of the latter toolkits, this study describes the development and application of the Terrestrial Plant Species Invasiveness Screening Kit (TPS-ISK). As a second-generation ISK tool, the TPS-ISK is a multilingual turnkey application that provides several advantages relative to the WRA: (i) compliance with the minimum standards against which a protocol should be evaluated for invasion process and management approaches; (ii) enhanced questionnaire comprehensiveness including a climate change component; (iii) provision of a level of confidence; (iv) error-free computation of risk scores; (v) multilingual support; (vi) possibility for across-study comparisons of screening outcomes; (vii) a powerful graphical user interface; (viii) seamless software deployment and accessibility with improved data exchange. The TPS-ISK successfully risk-ranked five representative sample species for the main taxonomic groups supported by the tool and ten angiosperms previously screened with the WRA for Turkey. The almost 20-year continuous development and evolution of the ISK tools, as opposed to the WRA, closely meet the increasing demand by scientists and decision-makers for a reliable, comprehensive, updatable and easily deployable decision support tool. For terrestrial plant screening, these requirements are therefore met by the newly developed TPS-ISK.

Asclepiasspeciosa (Apocynaceae, Asclepiadoideae): a rare or unrecognized alien species in Europe?

Studies on populations of Asclepiassyriaca L. in Lithuania revealed the occurrence of a new alien plant species, the North American native Asclepiasspeciosa Torr. (Apocynaceae, Asclepiadoideae), in southern parts of Lithuania - the first report of the latter species in Europe. Interestingly, a thorough analysis of herbarium specimens revealed that A.speciosa had first been collected in Lithuania in 1962, but the specimen was misidentified at the time as A.syriaca. The newly discovered population of A.speciosa occupies mesic grasslands, tall-herb fringe communities and arable field habitats. Sexual reproduction of this species was not recorded; it spreads locally by means of vegetative reproduction. We present here an exhaustive analysis of morphological characteristics and differences between A.speciosa and A.syriaca and other species of the genus, as well as a key for identification of alien Asclepias species in Europe. We predict that the effect of A.speciosa on native habitats and communities, and its economic impact, are comparable to those of the highly invasive A.syriaca. Although A.speciosa currently occurs very rarely as an alien species in Europe, its existence in other regions of Europe is highly probable.