The bromeliad family is large and various, containing three sub-families (Pitcairnioideae, Tillandsioideae and Bromelioideae) and about 1,500 American species. Members of the parent Bromeliaceae family greatly vary in size, color and shape. With relatively adaptable root systems, bromeliads grow in a wide range of natural habitats from the southwestern deserts of the United States to tropical rain forests near the equator. Some anchor their specialized roots in trees or rocks, others in the ground.