Firs (Abies) are a genus of between 45-55 species of evergreen conifers. Firs can be distinguished from other members of the pine family by their needle-like leaves, attached to the twig by a base that resembles a small suction cup; and by erect, cylindrical cones 5-25 cm (2-10 in) long that disintegrate at maturity to release the winged seeds.