The scientific name for palm trees is Arecaceae. They are found in USDA zones 8-10, and they are a tropical evergreen having a single trunk with tufts of foliage at the top of the trunk. Over 2,500 species of palm trees exist.
Palm trees existed over 80 million years ago during the late Cretaceous period. Two groups of palm trees evolved with different shaped leaves--feather, and fan-shaped.
The trunk can be smooth or it can have definitive scars, which mark where leaves were positioned before falling off the tree. The inside of the trunk is no different than other tree trunks.
The leaves of the palm tree grow out from the top of the trunk, and form the crown of the tree. The tops of the leaves eventually decay, and fall from the tree.
The flowers of the palm tree are in most cases very small and green in color. Flowering habits vary according to the species of palm tree.
The size of the fruit varies according to the species of palm tree. Some species have fleshy exteriors (date), and others have hard exteriors (coconut).