New woody alien plant species recorded in Lithuania

Abstract

Gudžinskas Z., Petrulaitis L., Žalneravičius E., 2017: New woody alien plant species recorded in Lithuania. -Bot. Lith., 23(2): 153-168.Many woody plant species that originate from various regions of the world have been introduced in other regions or continents and are used in ornamental gardening, silviculture, erosion control, for fruit sources or other purposes. Woody plants selected for introduction usually originate from regions with similar climate conditions; therefore, after certain time lag they start to spread outside places of cultivation, become naturalized or even invasive. In addition to 77 woody alien plant species reported in Lithuania, ten new species were recorded and analysed in this paper. Information on the native and anthropogenic ranges, first record in Lithuania, size of populations, habitats, reproduction and naturalization of Aralia elata, Berberis thunbergii, Caragana frutex, Celastrus orbiculatus, Cornus alba, Cytisus austriacus, Hydrangea arborescens, Pinus strobus, Rhus typhinaand Thuja occidentalis is presented. All these species have been introduced intentionally and are used mainly in ornamental gardening. Three of the reported species, Berberis thunbergii, Hydrangea arborescens and Thuja occidentalis, currently are casual species. Remaining seven species were recognized as naturalized in Lithuania, and five of these, i.e. Aralia elata, Celastrus orbiculatus, Cornus alba, Pinus strobus and Rhus typhina as well as Berberis thunbergii, which currently is treated as a casual, have very high or high probability of getting invasive. Constant survey of potential habitats, detection of new escaped alien plants, particularly of trees and shrubs, is the best way to reveal potentially dangerous species and make timely decisions for their control or eradication, if necessary.

Emerging invasion threat of the liana Celastrus orbiculatus (Celastraceae) in Europe

“…Our study, though based on only 12 sampled mature individuals, revealed that only monoecious individuals were present in the four studied populations in Lithuania. The fact that in all studied populations we found monoecious individuals explains the presence of a certain amount of ripe fruits (Gudžinskas et al 2017). Interestingly, in 2019 we recorded an individual of C. orbiculatus in Ķemeri (Latvia) with solitary fruits and we suppose that this plant is also monoecious with prevailing functionally male flowers.…”

“…Information on the distribution of C. orbiculatus in Europe was quite dispersed over numerous publications and other sources of information. According to these sources C. orbiculatus has been recorded in 13 European countries: Austria (Leonhartsberger 2013; Sauberer and Till 2015), Belgium (Verloove 2006(Verloove , 2013, the Czech Republic (Červinka and Sádlo 2000;Pyšek et al 2012;Pergl et al 2016), Germany (Brandes 2011;Adolphi et al 2012;Adolphi 2015;Alberternst 2018;Alberternst and Nawrath 2018), Latvia, Lithuania (Gudžinskas et al 2017), the Netherlands (Beringen et al 2017), Norway (Gederaas et al 2012;Beringen et al 2017), Poland (Purcel 2010(Purcel , 2011, the European part of Russia (Morozova 2014, without exact locality), Sweden (Beringen et al 2017), Ukraine and United Kingdom (Stace 1997;Beringen et al 2017;BSBI 2018). In total, 58 sites of occurrence of this species have been reported so far and they fall into 42 grid cells of the "Atlas Florae Europaeae" (Figure 3).…”

“…According to Adolphi et al (2012), this species was first reported to have escaped in Germany in the early 1950s near Lohr am Main, but was then erroneously identified as C. scandens. To date, C. orbiculatus has been recorded as a casual or naturalised species in 13 European countries (Stace 1997;Verloove 2006;Purcel 2010;Pyšek et al 2012;Tokarska-Guzik et al 2012;Leonhartsberger 2013;Adolphi 2015;Beringen et al 2017;Gudžinskas et al 2017;Alberternst and Nawrath 2018, etc. ).…”

“…Important results of several other investigations that have not been evaluated in the previous risk assessment (Beringen et al 2017) have revealed new important information about the invasiveness and performance of C. orbiculatus in the Baltic Region and in Central Europe (e.g. Purcel 2010Purcel , 2011Gudžinskas et al 2017;Alberternst and Nawrath 2018).…”

Additions and Corrections to the List of Alien Plant Species of Lithuania

“…More than thirty years have passed since the start of my studies in 1987 on alien plant species in Lithuania. During this time, more than 200 species of earlier non-registered alien plants have been discovered, and a lot of information on their distribution, naturalization, ecology and biology has been collected (Gudžinskas, 1989(Gudžinskas, , 1993(Gudžinskas, , 1994(Gudžinskas, , 1997a(Gudžinskas, , 2017Gudžinskas et al, , 2017. Some plant species have not been identified immediately, and only after several decades, with additional information gathered, it has become possible to determine their identity, although a small fraction of the samples collected so far have not been identified and this should be done in the future.…”