Lateral Root

A branch off the primary root. It is often small, but may be as large as the primary root.

Leaf Axil

The junction where a leaf attaches to a stem. See “axil.”

Leaf Blade

The expanded portion of a leaf. See “blade.”


A division of a compound leaf. For example, white clover leaves have three leaflets.

Leaf Margins

The edges of a leaf.

Leaf Sheath

In grasses, the lower portion of the leaf that surrounds the stem. It is below the blade. Grass sheaths may have open, closed or overlapping margins.


A plant in the Fabaceae family. This family is made up of broadleaf forbs that have a symbiotic relationship with rhizobia bacteria, which fix atmospheric nitrogen. Alfalfa, clovers, etc. are examples of legumes.


Together with the palea, the lemma encloses the grass flower or seed. Relative to the palea, the lemma is usually longer and attached lower to the outside of and with its edges overlapping the palea. The lemma may have an awn. Most grass seeds have the lemma and palea attached after threshing, e.g. bromegrass, fescue, wheatgrasses. The lemma and palea are sometimes called hulls.


In grasses, membranous tissue located between the stem and the leaf blade, near where the blade attaches to the sheath.


A medium textured soil composed of a desirable portion of sand, silt and clay.


Lodging is the breaking or bending of stems near the base so that the plants lie on the ground, often due to weak stems. Plant height, wall thickness and cell wall lignification can affect lodging. Tall plants have a higher tendency to lodge than short plants. Adverse weather conditions such as winds and heavy rains can cause lodging as well.