Forage Information System, Oregon State University
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Glossary

Define terms to be used throughout the site

a
abaxial
Located on the side away from the axis (e.g., the undersurface of a leaf).
abiotic
Nonliving components of the environment, such as water, solar radiation, oxygen, organic compounds, and soil nutrients.
abomasum
The fourth compartment of the ruminant stomach, comprising the true stomach, in which occur digestive processes similar to those found in the nonruminant stomach.
acceptability
Readiness with which animals select and ingest a forage; sometimes used interchangeable to mean either palatability or voluntary intake.
acid detergent fiber
Insoluble residue following extraction of herbage with acid detergent (ban Soest); cell wall constituents minus hemicellulose.Synonyms: ADF
acid detergent fiber digestibility
The digestibility of acid detergent fiber (ADF) of a forage, as determined by the percentage decrease in ADF measured before and after in vitro or in vivo digestion
acid detergent lignin
Lignin in the residue determined following extraction with acid detergent.Synonyms: ADL
acid pepsin
Used is second stage of in vitro forage digestion, 2 g of 0.1 g kg-1 pepsin in 1 L of 0.1 M HCI.
ad libitum feeding
Daily feed offerings that allow free-will consumption, generally fed to have a daily excess of 15% of feed remaining.
adaxial
Located on the side toward the axis (e.g., the upper surface of a leaf).
adventitious roots
The second root system which develops from the lower nodes of each grass tiller; seminal roots, the primary roots, develop from embryo primordia but are short lived.
aerobic
Pertaining to life or processes occurring in free oxygen or in oxygen concentrations normal in air (21% O2). See also anaerobic
aflatoxin C17H10O6
A polynuclear substance derived from molds; a known carcinogen. It is produced by a fungus occurring on peanuts, corn , and other plants, especially seeds.
aftermath
Residue and/or regrowth of plants (forage) used for grazing after harvesting of a crop.
agro-silvo-pastoral
Land use system in which woody perennials are grown with agricultural crops, forage crops, and livestock production.
agroforestry
Land use system in which woody perennials are grown for wood production in association with agricultural crops, with or without animal production, or other commercial enterprises.
agrostology
agrostology Study of grasses; their classification, management, and utilization.
alkaloid
One of a class of basic organic compounds with nitrogen in their structure; a secondary product of plant metabolism. An example is perloline, produced by tall fescue.
allelopathy
The positive or negative influence of living plant upon another due to secretion of chemical substances. See autotoxicity.
amylopectin
The form of starch in which branching occurs through alpha 1-6 linkages from an amylose backbone. Amylopectins are more easily dissolved and digested than amylose. The contents of amylose and amylopectins in seed grains are genetically controlled.
amylose
amylose The form of starch in which linkages are exclusively alpha 1-4. While representative formulas usually are presented in a linear fashion, the molecules actually have a spiral form.
anaerobic
anaerobic Living in the absence of free oxygen; the opposite of aerobic.
annual
annual A plant that completes its life cycle and dies within a year.
anoxia
Oxygen deficiency.
anthesis
Stage in floral development when pollen is shed from anthers. With self-pollinating species, anthesis occurs prior to the seapration of the lemma and palea.
antiquality constituents
Constituents that have negative effects on forage intake or that produce negative responses in animals consuming the produce containing the constituent.
apical dominance
Inhibiting effect of a terminal bud upon the development of lateral buds.
apomixis
Formation of viable embryos without actual union of male and female gametes, as in Kentucky bluegrass.
ash
The residue remaining after complete burning of combustible matter; consists mainly of minerals in oxidized form.
auricle
A leaf appendage; adjacent to the collar between the blade and the sheath, a claw-like lobe at the base of leaf blades of certain grass species.
autotoxicity
A specific type of allelopathy where the presence of adult plants interferes with the germination and development of its own seedlings.
awn
A stiff bristle. Used in the Asteraceae for a pappus of stout bristles or hard needle-like structures. Used in the Poaceae for the bristley appendages often borne on glumes and lemmas. Sometimes called a beard.
awned
Having an awn.
awnless
Not having an awn.
axillary bud
Meristematic apex located in the junction of the leaf and stem; gives rise to tillers in grasses and to branches and flowers in dicots.
axis
The middle of the structure (e.g., the rachis of a compound leaf, the center of a compound ovary).
b
bioassay
The use of living organisms to quantitatively estimate the amount of biologically active substances present in a sample.
biomass
The weight of living organisms (plants and animals) in an ecosystem at a given point in time, expressed either as fresh or dry weight.
blade
The part of a leaf of a grass or similar plant above the sheath, also known as the lamina.
bloat
Excessive accumulation of gases in the rumen of animals because loss through the esophagus is impaired, causing distension of the rumen.
bloom, early
Initial flowering (anthesis) in the uppermost portion of the inflorescence.Synonyms: early bloom
bloom, full
Essentially all florets in the inflorescence in anthesis.Synonyms: full bloom
blooming
Refers to anthesis in the grass family, or to the period during which florets are open and anthers are extended.
BNF
biological nitrogen fixation
boot stage
Growth stage when a grass inflorescence is enclosed by the sheath of the uppermost leaf.
bract
A modified or reduced leaf subtending a flower or inflorescence such as the glumes and lemmas.
brassica
Important species of brassica fall into three groups: turnips, B. rapa L., include common root crops and some rapes with turnip-like leaves; swedes, B. napus L., include not only the swedes proper but the common or oil bearing rapes; and cabbages, B. oleracea L., include the common vegetable and also the forage crops thousand-headed kale and marrowstem kale.
brown patch
brown patch Latin name Pellicularia filamentosa (Pat.) Rogers.
c
C3-plant
a plant employing ribulose bisphosphate carboxylase as the primary CO2-capturing enzyme, with the first product being a 3-carbon acid, also display photorespiration.
C4-plant
a plant employing phosphoenolpyruvate carboxylase as the primary CO2-capturing enzyme, with the first product being a 4-carbon acid, does not display photorespiration.
calorie (gram calorie)
The amount of heat required to raise the temperature of 1g of water one degree Celsius. One kilocalorie (kcal) = 1,000 calories; one megacalorie (Mcal) = 1,000,000 calories.
canopy
canopy The aerial portion of plants in their natural growth position; usually expressed as percent of ground so occupied or as leaf area index.
carbohydrate
Compound of carbon, hydrogen, and oxygen in the ratio of CH2O, as in sugar, starch, and cellulose.
carbohydrates, nonstructural
Soluble carbohydrates found in the cell contents, as contrasted with structural carbohydrates in the cell walls. Assumed to be available to support life processes.
carbohydrates, structural
Carbohydrates found in the cell walls (e.g. hemicellulose, cellulose); assumed to not be available to support life processes.
caryopsis
Small, one-seeded, dry fruit with a thin pericarp surrounding and adhering to the seed; the ripened fruit of grasses, a single seed or kernel of grain.
cecum
Intestinal pouch located at the junction of larger and small intestines of non-ruminants. Functions somewhat similar to a rumen. Usually it is much larger in the hebivorous horse than in the nonherbivorous monogastrics.
cell wall constituents
Compounds that make up or constitute the cell wall, including cellulose, hemicellulose, lignin, and minerals (ash).
cell wall content
The proportion of plant material made up of cell walls as opposed to cell contents, usually determined by solubility differential.
cellulase
Enzymes that digest cellulose to hexose units.
cellulose
A carbohydrate formed from glucose that is linked by beta 1, 4 bounds, a major constituent of plant cell walls. a colorless solid; insoluble in water.
certified
Meeting a specified standard.
climatologist
One versed in, or who studies, climatology.
climatology
The meteorological study of climates and their phenomena
coated seed
Seed for planting purposes to which a substantial amount of foreign material is used to cover each seed to make the seed uniform in size and shape and free-flowing, or to serve as a carrier of fertilizer, pesticides, nitrogen-fixing microorganisms, coloring, or other additives. Synonym: pelleted seed.
collar
A thin band of meristematic tissue at the junction of the leaf blade and sheath in grasses.
coloration
Arrangement of colors.
companion crop
A crop such as a small grain that is sown with another crop, especially one that will emerge and develop slowly, such as a forage crop. Preferred to the term nurse crop.
concentrate
All feed, low in fiber and high in total digestible nutrients, that supplies primary nutrients (protein, carbohydrate, and fat); for example, grains, cottonseed meal, wheat bran.
continuous stocking
A method of grazing livestock on a given unit of land where animals have unrestricted and uninterrupted access throughout the time period when grazing is allowed. Usage: Specify the length of the grazing period.
cool-season grass
Grass species that grow best during cool, moist periods of the year; they commonly have temperature optimums of 15 to 25'C (59 to 77'F.)
coumarin
A white, crystalline compound with a vanilla-like odor that gives sweetclover its characteristic odor. An antiquality component of sweetclover.
coumestrol
Estrogenic factor occurring naturally in forage crops, especially in ladino clover, strawberry clover, and alfalfa.
crimped
Rolled with corrugated rollers, especially fresh forage, to break stems and facilitate drying.
crown
Base or stem where roots arise.
crown rust
Latin name Puccinia coronata Cda.
crude fiber
Coarse, fibrous portions of plants, such as cellulose, that are partially digestible and relatively low in nutritional value. In chemical analysis, it is the residue obtained after boiling plant material with dilute acid and then with dilute alkali. Term is being replaced with more specific NDF (neutral detergent fiber) and ADF (acid detergent fiber). Coarse, fibrous portions of plants, such as cellulose, that are partially digestible and relatively low in nutritional value. In chemical analysis, it is the residue obtained after boiling plant material with dilute acid and then with dilute alkali. Term is being replaced with more specific NDF (neutral detergent fiber) and ADF (acid detergent fiber). Coarse, fibrous portions of plants, such as cellulose, that are partially digestible and relatively low in nutritional value. In chemical analysis, it is the residue obtained after boiling plant material with dilute acid and then with dilute alkali. Term is being replaced with more specific NDF (neutral detergent fiber) and ADF (acid detergent fiber).
cubing
Process of forming hay into high-density cubes to facilitate transportation, storage, and feeding.
culm
The central axis of the flowering shoot of grasses, comprised of distinct nodes and internodes, each node bearing a leaf. The upper-most culm internode supporting the seed head is called the peduncle.
cultivar
(1) A variety, strain, or race that has originated and persisted under cultivation or was specifically developed for the purpose of cultivation. (2) For cultivated plants, the equivalent of botanical variety, in accordance with the International Code of Nomenclature of Cultivated Plants--1980.
cuticle
a waxy layer secreted by epidermal cells on the outer surface on plants.
cutin
A way layer secreted by epidermal cells on the outer surface on plants.
cyanogenesis
The release of hydrocyanic acid (HCN) in the process of chemical change. Cyanogenetic is the adjective form.
d
decapitation
Untimely defoliation of a developing flowering culm in a manner which removes the shoot primordium.
denuding
Defoliation which severes a grass shoot above the developing floral bud (growing point) but beneath the collar zone of a majority of the exposed leaf blades.
desiccant
A drying agent
digestibility (apparent)
apparent: Digestibility determined by animal feeding trials, calculated as feed consumption minus excretion (feces), expressed as percent; does not account for endogenous excretions in the feces.
digestibility (true)
true: Actual digestiblity or availablility of feed, forage. or nutrient as represented by the balance between intake and fecal loss of the same ingested material with endogenous excretions in feces accounted for; in vitro digestibility without adjustment to in vivo base.
diploid
A tissue or plant with two sets of chromosomes in each cell (characterestic of sporphytes).
dough stage
Seed development stage at which endosperm development is pliable, like dough (e.g., soft, medium, hard); usually used when 50% of seeds on an inflorescence are in this stage of development.
dry matter (DM)
The substance in a plant remaining after oven drying to constant weight at a temperature slightly above the boiling point of water.
e
early bloom
Initial flowering (anthesis) in the uppermost portion of the inflorescence.Synonyms: bloom, early
f
Frequently Asked Questions
full bloom
Essentially all florets in the inflorescence in anthesis.Synonyms: bloom, full