Which grass is which?
Plant identification can be challenging, especially plant identification of grasses. Land managers, farmers, naturalists, and gardeners want to know which grass is which so you can manage undesirable grasses and promote desirable ones. Illinois Extension can help you learn which grasses have wildlife or forage benefits, are potentially harmful if left untreated, and if they need to take action.
Let's start with the basics.
To identify grasses, there are some terms you should be familiar with. We can divide them into vegetative and flowering characteristics. Keep this handy grass identification guide handy.
Vegetative Characteristics
Stems
The vegetative portion of the grass consists of the stem, also known as the culm. The stem is the main backbone of the grass. Stems can be smooth or hairy, and sometimes they can have a whitish powder on them, making them glaucous.
Leaves
Grasses have leaves, but what you may think of as a traditional leaf is just one part of a grass leaf. Grass leaves include the blade, which is what we typically call a leaf, a sheath, which is a continuation of the leaf blade that wraps around the stem, and a node, which is a swelling that looks like a joint, and is located at the base of a leaf sheath. Leaf sheaths can be wrapped tightly around the stem and overlap, or they can be "open," appearing to not wrap completely around the stem.
Collar
The region where the leaf blade becomes the sheath is known as the collar region. This is a great first place to look when identifying a grass, because oftentimes there are structures located here that serve as key identification features when telling one grass apart from another. These structures include ligules, auricles, and horns.
