Increaser Species

Increaser rangeland plant species tend to increase in abundance and take the place of the decreaser species under continued heavy grazing pressure. The increasers will also begin to decrease when heavy and close grazing continues on an on-going basis.


Indeterminate growth is growth that is not terminated once a genetically pre-determined structure has completely formed as it does when the growth is determinate. A plant that grows and produces flowers until killed by frost or some other external factor is called indeterminate. These plants have flowers on lateral branches, enabling the stem to continue vegetative growth. Indeterminate plants flower over an extended period. Examples include alfalfa and alsike clover.


The flowering structure of a plant or the arrangement of the flowers of a plant. The inflorescence can be a head, raceme, spike, panicle, etc.


The application of nitrogen-fixing rhizobia bacteria to the seed of legumes. These bacteria are forage species specific or may be appropriate for a group of forage legumes. For example, the same rhizobia species can be used for alsike, red and white clover.


The portion of a stem between the nodes. Internodes lengthen as grass stems grow and elongate.

Introduced Forage

A species that is not naturally present in the vegetation of an area but that is brought in from another country or region, e.g. alfalfa.

Invader Species

Plants that are absent from climax rangeland, but will invade under disturbance or continued overuse.

IVDMD – In Vitro Dry Matter Disappearance

A method of estimating the dry matter lost following the incubation of the forage in rumen micro flora in the laboratory. IVDMD is expressed as a percentage of the initial sample and is a measurement of the digestibility of the forage.

IVDOM – In Vitro Digestible Organic Matter

In vitro digestibilities are determined in a laboratory using rumen microflora in a test tube. IVDOM refers to the proportion of the forage organic matter digested by the animal. It is generally expressed as a percentage and is used as a measure of digestibility.