Table S1: List of species present in control (non-invaded) and invaded by A. altissima plots. Life form and their level of abundance is also included in the table.

Species / Life form* / Abundance§ / Control / Invaded
Adiantum capillus-veneris L. / G / C / ✓ / -
Agrimonia eupatoria L. subsp. eupatoria / H / M / ✓ / -
Agrostis stolonifera L. / G / C / - / ✓
Ailanthus altissima (Mill.) Swingle / M/Me / E / - / ✓
Allium sphaerocephalon L. / G / C / ✓ / ✓
Andryala integrifolia L. / T/H / M / ✓ / -
Arctium minus (Hill) Bernh. / H / M / ✓ / -
Aristolochia paucinervis Pomel / G / M / ✓ / -
Asparagus acutifolius L. / C/N / C / ✓ / ✓
Asperula aristata subsp. scabra (J. and C. Presl) Nyman / C/H / C / ✓ / ✓
Avena sp. / G / - / ✓
Bituminaria bituminosa (L.) C. H. Stirt. / C/H / C / ✓ / ✓
Brachypodium phoenicoides Roem. and Schult. / H/G / CC / ✓ / ✓
Brachypodium retusum (Pers.) Beauv. / H/G / CC / - / ✓
Bromus diandrus Roth / T / C / - / ✓
Bromus sp. / G / - / ✓
Bryonia dioica Jacq. / H / M / - / ✓
Buglossoides arvensis (L.) I. M. Johnst. / T / C / ✓ / ✓
Carex flacca Schreb. / G / C / ✓ / ✓
Carex mairii Coss. and Germ. / H / M / ✓ / -
Catananche caerulea L. / H / M / ✓ / -
Celtis australis L. / M / E / ✓
Centaurea aspera L. subsp. aspera / H / CC / ✓ / -
Cephalanthera damasonium (Mill.) Druce / G / R / ✓ / -
Cichorium intybus L. / H / C / ✓
Cirsium monspessulanum (L.) Hill. subsp. ferox (Coss.) Talavera / H / C / ✓ / -
Cistus albidus L. / N / C / ✓ / -
Convolvulus arvensis L. / G / CC / ✓
Conyza sumatrensis (Retz.) E. Walker / H / -
Corylus avellana L. / M / R / ✓ / -
Crataegus monogyna Jacq. / Me / C / ✓ / ✓
Cynoglossum cheirifolium L. / H / C / - / ✓
Daphne gnidium L. / N / C / ✓ / ✓
Daucus carota L. subsp. carota / H / CC / ✓ / ✓
Dittrichia viscosa (L.) Greuter / C / CC / ✓ / -
Epilobium sp. / H / ✓ / -
Equisetum ramosissimum Desf. / G / CC / ✓ / ✓
Eryngium campestre L. / H / CC / - / ✓
Euphorbia sp. / H / ✓ / -
Festuca arundinacea Schreb. subsp. fenas (Lag.) Arcang. / H / M / ✓ / -
Ficus carica L. / Me / C / ✓ / ✓
Foeniculum vulgare Mill. subsp. piperitum (Ucria) Cout. / H / C / ✓ / ✓
Fraxinus ornus L. / M / M / ✓ / -
Galium aparine L. / T / C / - / ✓
Galium spurium L. / T / M / - / ✓
Genista scorpius (L.) DC. / N / C / ✓ / -
Geranium rotundifolium L. / T / CC / - / ✓
Hedera helix L. / P / C / ✓ / ✓
Helichrysum italicum subsp. serotinum (Boiss.) P. Fourn. / C / C / ✓ / -
Humulus lupulus L. / P / RR / - / ✓
Hypericum perforatum L. / H / C / ✓ / -
Juglans regia L. / M / M / ✓ / -
Juncus subnodulosus Schrank / G / M / ✓ / ✓
Lonicera etrusca G. Santi / P / M / - / ✓
Marrubium vulgare L. / H / C / ✓ / ✓
Matthiola fruticosa (L.) Maire / C / C / ✓ / -
Medicago minima (L.) L. / T / C / ✓ / -
Medicago sativa L. / H / CC / - / ✓
Medicago suffruticosa Ramond ex DC. / C/M / C / ✓ / -
Mentha suaveolens subsp. suaveolens (L.) Hudson / H / C / ✓ / ✓
Mentha sp. / H / - / ✓
Mercurialis tomentosa L. / C / M / ✓ / -
Origanum vulgare L. subsp. virens (Hoffmanns. and Link) Bonnier and Layens / H / M / ✓ / -
Osyris alba L. / N / C / ✓ / -
Oxalis corniculata L. / H / C / - / ✓
Pallenis spinosa (L.) Cass. / H / C / ✓ / ✓
Parietaria judaica L. / H / CC / - / ✓
Pinus halepensis Mill. / M / CC / ✓
Piptatherum miliaceum (L.) Coss. subsp. miliaceum / H / C / ✓ / ✓
Plantago lanceolata L. / H / C / ✓ / ✓
Polygala monspeliaca L. / T / M / ✓ / ✓
Populus nigra L. / M / CC / ✓ / ✓
Potentilla reptans L. / H / C / ✓ / -
Prunus domestica L. / M / R / ✓ / -
Prunus spinosa L. / N/Me / M / ✓ / ✓
Pulicaria dysenterica (L.) Bernh. / H / C / ✓ / -
Quercus coccifera L. / Me/N / CC / ✓ / ✓
Quercus ilex L. subsp. ballota (Desf.) Samp. / M / C / ✓ / ✓
Rhamnus alaternus L. / N/Me / CC / ✓ / ✓
Robinia pseudoacacia L. / M / E / - / ✓
Rosa canina L. / P / R / ✓ / ✓
Rosmarinus officinalis L. / N / CC / ✓ / -
Rubia peregrina L. subsp. peregrina / P / C / ✓ / ✓
Rubus ulmifolius Schott / P / CC / ✓ / ✓
Salix atrocinerea Brot. / Me / M / ✓ / -
Salvia verbenaca L. / H / M / ✓ / -
Sambucus nigra L. / Me / M / ✓ / ✓
Scabiosa atropurpurea L. / H / M / ✓ / -
Scirpus holoschoenus L. / G / CC / ✓ / -
Scrophularia auriculata L. subsp. valentina (Rouy) Ortega Oliv., Serra, Herrero & Muñoz Garm. / H / C / ✓ / -
Silybum marianum (L.) Gaertn. / H / M / ✓ / ✓
Smilax aspera L. / P / C / ✓ / ✓
Solanum dulcamara L. / P / M / ✓ / ✓
Sonchus maritimus L. subsp. aquatilis (Pourr.) Nyman / H / C / ✓ / -
Torilis arvensis (Huds.) Link subsp. neglecta (Spreng.) Thell. / T / C / ✓ / -
Torilis sp. / T / ✓ / ✓
Trachelium caeruleum L. / H / M / ✓ / -
Trifolium repens L. / H / C / ✓ / -
Trifolium sp. / H / ✓ / ✓
Ulex parviflorus Pourr. / N / C / ✓
Ulmus minor Mill. / M / C / ✓ / ✓
Urtica urens L. / T / CC / - / ✓
Verbascum sp. / H / ✓ / -
Viburnum tinus L. / Me / M / ✓ / ✓
Vicia sp. / H / ✓ / ✓
Viola alba Besser / H / M / ✓ / -

*C: chamaephyte, P: phanerophyte, G: geophyte, H: hemicryptophyte, M: macrophanerophyte, Me: mesophanerophyte, N: nanophanerohyte, T: therophyte

§ CC: very common, C: common, E: exotic, M: medium abundance, R: rare, RR: very rare

Table S2: Correlation (Spearman´s r) matrix among the functional variables measured

Available Phosphorus / b-glucosidase / Phosphatase / Understory biomass
Soil organic matter / r / 0.34 / -0.12 / 0.08 / 0.20
P-value / 0.146 / 0.602 / 0.729 / 0.401
Available Phosphorus / r / -0.25 / -0.07 / 0.13
P-value / 0.298 / 0.777 / 0.596
b-glucosidase / r / -0.34 / 0.00
P-value / 0.143 / 0.985
Phosphatase / r / -0.44
P-value / 0.055


Figure S1: Distribution map of Control (red points) and Ailanthus plots (yellow points).

Figure S2: Evolutionary relationships among the sampled species. Highlighted in grey are those species abundant in control plots (≥50% of the plots) but absent in plots invaded by A. altissima.

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