No, you guys are getting colder… That olive-green lichen tends to like these trees' trunks. Not sure if that helps, but I see that color lichen on these more than other trees.
No, not a Linden at all, but similar qualities as mentioned. Leaves, buds, fruit, lots of similarities IMO. This is an introduced tree with native relatives.
Leaves are toothed and cordate, like Linden. Seeds are samaras, like Linden. Buds and twigs are strongly alternate, with roundish, red, swelling buds, like Linden. Tree is an introduced species with native cousins.