In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height. In wider definitions, the taller palms, tree ferns, bananas, and bamboos are also trees.
Common ash (Fraxinus excelsior), a deciduous broad-leaved (angiosperm) tree
European larch (Larix decidua), a coniferous tree which is also deciduous
Tall herbaceous monocotyledonous plants such as banana lack secondary growth, but are trees under the broadest definition.
The Daintree Rainforest
A stem is one of two main structural axes of a vascular plant, the other being the root. It supports leaves, flowers and fruits, transports water and dissolved substances between the roots and the shoots in the xylem and phloem, photosynthesis takes place here, stores nutrients, and produces new living tissue. The stem can also be called halm or haulm or culms.
Stem showing internode and nodes plus leaf petioles
This above-ground stem of Polygonum has lost its leaves, but is producing adventitious roots from the nodes.
Climbing stem of Senecio angulatus.
Decumbent stem in Cucurbita maxima.
