Fasciation is a deformity in plants resulting in flattened, thickened, elongated stems. The emerging flowers can be stunted and distorted, overcrowded, and undersized.

Fasciation is caused by many things, such as bacteria, viruses, and genetic mutation. Only some forms of fasciation are infectious.

Commonly fasciated specimens include daisies, roses, and petunias, but all plants can exhibit fasciation.

The appearance of fasciated plants can be considered desirable by botanists and certain fasciated species are bred and collected for their aesthetic, including willows and cockscombs.

Tickseed showing fasciation symptoms.

A fasciated dandelion.