Bromeliad is the common name given to the plant family Bromeliaceae. One popular subfamily that makes up the Bromeliaceae is the Bromelioideae, which includes the fruit pineapple. Two other subfamilies that have been acknowledged are the Tillandsioideae and Pitcairnioideae. The three subfamilies are fairly diverse and are distinguished mainly by geography and growth patterns.
Considered to be tropical plants, the monocot bromeliad plants can be found from the southern border of the United States through almost all of South America. The Pitcarirnia feliciana species is an exception to this geographic distribution, as they are not native to the Americas. Instead, this species originated from parts of West Africa.
Species of bromeliad are quite diverse and can vary greatly in appearance and climatic preference between the subfamilies. The foliage of bromeliads exhibits a wide variety of hues, featuring greens and lighter shades like cream. Other bromeliads have vibrant magentas and deep golden yellows.
Regardless of species, most bromeliads follow a rosette pattern where the leaves grow in a disc-shaped formation. The foliage, which originates from a single level on the plant, may be thin or wide, short or long. The leaves can have different textures, such as prickly or smooth.
The flower arrangement of the bromeliad family, its inflorescence, is equally varied. The height and length of the inflorescence can be a tenth of an inch (3 mm) in some species to nearly a dozen yards (about 10-12 meters) in others. The inflorescence on other bromeliad plants never manifests outwardly because its flowers develop within the stalks near the roots.
The three bromeliad subfamilies each exhibit a distinct type of root system. Bromelioideae is largely made up of epiphytes, plants whose roots latch on to other plants, most commonly trees, but derive no nutritional value from their base.
Unlike most of its epiphytic subfamily, the pineapple exhibits terrestrial tendencies, rising instead from the ground and gathering nutrients from the earth. The pineapple is grown for human consumption on a world-wide scale, the only bromeliad to be cultivated for commercial use. As such, the pineapple's most common usage is for food, but it is also used for textile fiber and for medicine in the Philippines.
Pitcairnioideae are terrestrial, mostly using the soil as their base and source of nutrients, and tend to favor dry landscapes. Pitcairnioideae plants have adapted to water-deprived terrains by developing the ability to retain water within their stalks and foliage. They grow spines, like some other bromeliad species, that further protect them from otherwise inhospitable climates.
The Tillandsioideae subfamily can be either epiphytic or lithophytic. Like the Bromelioideae, they receive much of their sustenance from the moisture present in the surrounding atmosphere. The most familiar member is the Spanish moss, which is not related to moss species or lichens.