Grasses

Most grasses are annual plants or are herbaceous perennials that die back to the ground surface at the end of the growing season and then regenerate the next season by shoots developing from underground rhizome or root systems. A few species, such as the bamboos, develop as shrub- and tree-sized, woody plants.

The shoots of grasses typically have swollen nodes, or bases, and they are often hollow between the nodes. The leaves are usually long and narrow and have parallel veins. A specialized tissue called a ligule is usually present at the location where a leaf sheaths to the stem. The flowers of grasses are typically small, monoecious or dioecious, and are called florets. The florets have various specialized tissues, and often contain a long bristle called an awn, which can be quite prominent in some species. The florets are generally arranged into an inflorescence, or cluster, which can be quite large in some species. Pollination of grasses occurs when grass pollen is shed to the wind and carried opportunistically to other grasses. The fruits of grasses are known as a caryopsis or grain, are one-seeded, and can contain a large concentration of starch.