What do you call a stem that grows below the soil surface?

A stem that grows below the soil surface is referred to as a rhizome. This type of stem has the characteristic of being horizontally oriented and can spread out and produce new shoots and roots from its nodes, which allows for vegetative reproduction. Rhizomes serve as storage organs and help plants survive adverse conditions by preserving energy and nutrients underground.

In contrast to rhizomes, corms, bulbs, and tubers all have different structures and functions. Corms are swollen underground stems that store food, but they grow vertically and produce new plants at the top rather than from the sides. Bulbs consist of a short stem surrounded by fleshy leaves that store nutrients; they typically reproduce through the production of offsets rather than horizontal growth. Tubers, such as potatoes, are also swollen underground stems that serve as storage organs, but they develop from a single growing point and primarily grow in a vertical manner.

Understanding the distinction of these structures helps in identifying and managing various types of plants and their growth habits effectively within the field of pest management.