The stem is the main trunk of a plant. Buds and shoots develop on stems. Stems provide structure and support for leaves, flowers and fruits. They also carry nutrients and water. In some cases, stems also store food.
Stems are generally upright and above ground, easy to locate and identify.
However, there are many stems that grow below ground or are ground hugging. These stem modifications include corms, bulbs, rhizomes, runners, stolons, tubers and crowns. A modified stem is recognizable because it includes buds and sometimes leaves. Internodes are the segments of the stem between nodes. The quality and amount of available light and temperature affect the length of the internode.