Gleditsia
Tree originating from North America with thin and large foliage, with trunk and branches covered in thorns that goes from 8 to 20 cm (except for G. triacanthos “Inermis”). The deciduous leaves are composed by 20-30 leaflet, whose colour depend on the variety. In May it produces discrete flowers, while the fruits are brown and showy, up to 45 cm long. It can grow in dry and calcareous soils, and it is used for parks and avenues.