*3.1. The Lichen Biota in the Study Area*

In total, 148 lichen species were found in the 106 sampled trees (see Table S2): 89 species with sexual reproduction (60%) and 59 with vegetative reproduction (40%). Of the latter, 43 were sorediate and 16 were isidiate species. Most of the species (106 out of 148) were present in under 20% of the plots, with 34 species (23%) distributed in only one plot, while 16 lichens were present in more than 50% of the plots. Most of the lichens were nationally rare (92 species, 62%; 47 rare and 45 very rare), while common lichens represented 38% of the species pool (56 species; 42 common and 14 very common). Fifteen percent (22 species) of the floristic list was represented by lichens included in the Italian Red List: one Endangered species (*Alyxoria ochrocheila*), 4 Vulnerable species (*Agonimia allobata*, *Solitaria chrysophthalma*, *Sticta limbata*, *Vahliella saubinetii*), 11 Near-Threatened species (*Arthopyrenia salicis*, *Buellia disciformis*, *Caloplaca herbidella*, *Diarthonis spadicea*, *Lobarina scrobiculata*, *Nephroma resupinatum*, *Pachyphiale carneola*, *Pectenia plumbea*, *Ricasolia amplissima*—chloromorph, *Ricasolia amplissima—*cyanomorph, *Schismatomma ricasolii*), 4 Least Concern species (*Gyalecta liguriensis*, *Lobaria pulmonaria*, *Parmeliella testacea*, *Ramalina subgeniculata*), and two Data-Deficient species (*Lepra slesvicensis*, *Ochrolechia dalmatica*)
