Field Bio - Grass Anatomy

For Hocking College WLM-2212, Eco & Mgt of Grassland Wildlife.

Culms

The main stem of a grass plant. Typically hollow between the nodes and support the leaves and flowering structures.

Node

The joint on the culm where leaves, branches, or roots may arise. Usually solid and slightly swollen compared to the what?

Internodes

The segments of the stem between the what?

Blade

The flattened, usually strap-shaped upper portion of the leaf. It extends outward from the sheath and is the part most responsible for photosynthesis.

Sheath

The lower part of the leaf that wraps around the culm. It can be open, closed, or overlapping and protects the stem.

Collar

The region on the back of the leaf where the sheath transitions into the blade. It often looks like a thin band and may be divided into a left and right half

Ligule

A small appendage on the inner side of the leaf at the junction of the blade and sheath. It can be a membrane, a fringe of hairs, or absent—useful for identification.

Auricle

Small ear-like projections that may extend from the collar and wrap partly around the culm. Present or absent depending on species; helpful for identification.

Tiller

A new shoot that arises from a basal node of the plant. Can form clumps and help the grass spread and become denser.

Stolon

A horizontal, above-ground stem that grows along the soil surface and forms new plantlets at the nodes. Helps grasses spread vegetatively.

Rhizome

A horizontal, underground stem that produces roots and new shoots at its nodes. Allows grasses to spread and regenerate after disturbance.

Root

The below-ground organ that absorbs water and nutrients and anchors the plant. For grass, these are fibrous and form dense mats.

Inflorescence

Usually a panicle, spike, or raceme composed of spikelets. Each spikelet contains: Glumes (pair at base) Lemmas & Paleas (flower bracts) Florets (flowers with stamens & pistil)