Here's why:

* Herbaceous plants are typically soft-stemmed and die back to the ground at the end of the growing season.

* They lack the woody tissue that gives trees and shrubs their strength and rigidity.

* Examples include flowers, grasses, ferns, and many vegetables.

There are also other terms used to describe plants that don't produce wood, depending on their specific characteristics:

* Non-woody plants: This is a broad term that encompasses all plants without wood, including herbaceous plants and other types.

* Annuals, biennials, and perennials: These terms refer to the lifespan of the plant, not necessarily the presence or absence of wood. Many annuals and biennials are herbaceous, while some perennials are woody.