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This is online supplementary material for the Chapter "Australian Acacia species in Europe" authored by E.Marchante, A.C Gouveia, G. Brundu and H.Marchante, corresponding to Chapter 10In: "Wattles: Australian Acacia species around the world". Eds: D.M. Richardson, J.J. Le Roux, and E. Marchante (CABI, UK, 2023).

This is online supplementary material for the Chapter "Management of invasive Australian Acacia species in the Iberian Peninsula" authored by E.Marchante, C.M. Colaço, I.Skulska, F. Ulm, L.González, L.N. Duarte, S. Neves, C.Gonçalves, S.Maggiolli, J.Dias, C.Máguas, N.Fernandes, L.Fernandesand H.Marchante, corresponding to Chapter 27In: "Wattles: Australian Acacia species around the world". Eds: D.M. Richardson, J.J. Le Roux, and E. Marchante (CABI, UK, 2023).

This is online Supplementary material for the Chapter "Ecological impacts and changes in ecosystem services and disservices mediated by invasive Australian Acacia species " authored by D Le Maitre et al., corresponding to Chapter 22 In: "Wattles: Australian Acacia species around the world". Eds: D.M. Richardson, J.J. Le Roux, and E. Marchante (CABI, UK, 2023).

Conservation of biodiversity in protected areas is often threatened by invasive alien plants (IAPs), and its successful management requires proper planning, resources, and monitoring to adjust future interventions. Although follow-up controls and evaluation of different management actions through monitoring programs are crucial in an adaptive management strategy, they are often neglected. Acacia longifolia is one of the most widespread IAPs in the Portuguese coastal areas, causing several negative impacts. This study reports the results of different control methods of A. longifolia in two forest plantations over coastal dunes in two protected sites in Portugal, under different management regimes and for over 4 years. The best results were achieved after hand pulling, but due to its high cost, this method is not suitable for large areas. Mechanical cuts, which include the use of brush hogs, brush cutters, and chainsaws, resulted in variable levels of resprouting of A. longifolia stumps. Follow-up treatments, whether mechanical and/or chemical, reduced the number of A. longifolia resprouts and kept its cover below 20% and height below 50 cm. Furthermore, controlling with brush cutters/hogs reduced the seed bank of A. longifolia by 74% while that with a disc harrow allowed an even greater reduction (91%). In areas where no follow-up treatments were carried out, A. longifolia started producing flowers two and a half years after the initial treatment, restarting the cycle of seed production. Nevertheless, a biological control agent that reduces A. longifolia seed production (Trichilogaster acaciaelongifoliae) establishment was confirmed in the controlled areas, suggesting that new seed production by these plants will be soon controlled. Although species characteristic of the protected habitats are currently poorly represented, it is expected that they begin to emerge with the reduction of A. longifolia. Our results stress the importance of persistence of follow-up treatments if higher success in IAPs control is to be achieved, not only because of the resprouting ability of many species (despite this not being very common in A. longifolia) but also because invasive plants can produce extensive persistent seed banks. The role of the management regime on the level of success in controlling IAPs will be discussed.

In the context of global change, the integration of non-native tree (NNT) species into European forestry is increasingly being discussed. The ecological consequences of increasing use or spread of NNTs in European forests are highly uncertain, as the scientific evidence is either constraint to results from case studies with limited spatial extent, or concerns global assessments that lack focus on European NNTs. For either case, generalisations on European NNTs are challenging to draw. Here we compile data on the impacts of seven important NNTs (Acacia dealbata, Ailanthus altissima, Eucalyptus globulus, Prunus serotina, Pseudotsuga menziesii, Quercus rubra, Robinia pseudoacacia) on physical and chemical soil properties and diversity attributes in Europe, and summarise commonalities and differences. From a total of 103 publications considered, studies on diversity attributes were overall more frequent than studies on soil properties. The effects on soil properties varied greatly among tree species and depended on the respective soil property. Overall, increasing (45%) and decreasing (45%) impacts on soil occurred with similar frequency. In contrast, decreasing impacts on biodiversity were much more frequent (66%) than increasing ones (24%). Species phylogenetically distant from European tree species, such as Acacia dealbata, Eucalyptus globulus and Ailanthus altissima, showed the strongest decreasing impacts on biodiversity. Our results suggest that forest managers should be cautious in using NNTs, as a majority of NNT stands host fewer species when compared with native tree species or ecosystems, likely reflected in changes in biotic interactions and ecosystem functions. The high variability of impacts suggests that individual NNTs should be assessed separately, but NNTs that lack European relatives should be used with particular caution.