Nice pics. Yes, this is a large-leaved _Paulownia tomentosa_
sapling or sucker shoot. Tropical looking, isn't it? They remind
me of Balsa wood saplings I've seen in Costa Rica [they have
similarly large, similarly-shaped leaves].
If you leave it be, it will eventually change to become a much
smaller-leaved [but still pretty large], spring-flowering, branched
tree [they're actually rather attractive flowering trees; it's too
bad that they tend to invade natural habitats].
