Illinois Native Plant Guide

Glossary

Achene: a dry, single seeded fruit that doesn’t split at maturity, similar to a small nut.

Adventive: an exotic plant that is introduced and naturalized.

Allelopathic: any direct or indirect harmful effect of chemicals from one plant on nearby plants.

Annual Plant: a plant that completes its life cycle and dies in one year or less.

Arch Abutment: the part of an arch that directly receives thrust or pressure.

Best Management Practices (BMPs): A practice or combination or practices that are determined to be the most effective and practicable means of controlling point and non-point source pollutants. BMPs include structural devices which temporarily store or treat urban stormwater runoff to remove pollutants, reduce flooding, and protect aquatic habitats. BMPs also include non-structural approaches, such as public education efforts to prevent the dumping of household chemicals into storm drains.

Biennial Plant: a plant that lives for tow years, producing vegetative growth the first year, usually blooming and fruiting in the second year, and then dying.

Bog: a wetland with extensive peat accumulation and a low pH (acid).

Brackish: slightly salty; term applied to water with a saline content that is intermediate between that of freshwater and sea water.

Broadcast: to cast seed widely over the surface of the soil.

Buffer: A protected strip of land along the edge of a stream, lake, or wetland; usually maintained in natural or native vegetation. Buffers provide wildlife habitat, protect shores and banks from erosion, filter water pollutants, and screen sensitive areas from potential adverse effects of development activity.

Buttress Pile: a pile (pier) that supports or strengthens something.

Calcareous: possessing a sufficient quantity of free calcium carbonate or magnesium carbonate to effervesce carbon dioxide visibly when treated with cold 0.1 normal hydrochloric acid; which contribute to a basic condition.

Corm: a short, vertical, often swollen, underground stem, many “bulbs” are actually corms.

Detention Basin: a stormwater facility for storing runoff, with a controlled release of water during and after the rainfall event.

Division: plant propagation by dividing a parent plant into 2 or more. Many parts of plants can be split, including roots, crowns, bulbs, leaves, fronds, etc.

Drawdown: when the water level in a marsh or pond is lowered to expose the bottom sediment.

Drill: sowing seed in rows, usually by machine. The advantage is in more careful spacing of seed and assured seed-soil contact.

Emergent: a rooted, herbaceous, wetland or aquatic plant which manifests some of its adult growth above the waterline, but is rooted underwater.

FAC (Facultative): an indicator category for plants, estimating the probability of a given species to occur in wetlands at 34% to 66%. A positive (+) sign attached to the category indicates a frequency toward the higher end of the probability, and a negative (-) sign indicates a frequency toward the lower end of the probability. The indicator category does not equate to the degrees of wetness tolerated by a given species.

FACU (Facultative Upland): an indicator category for plants, estimating the probability of a given species to occur in wetlands at 1% to 33%. A positive (+) sign attached to the category indicates a frequency toward the higher end of the probability, and a negative (-) sign indicates a frequency toward the lower end of the probability. The indicator category does not equate to the degrees of wetness tolerated by a given species.

FACW (Facultative Wetland): an indicator category for plants, estimating the probability of a given species to occur in wetlands at 67% to 99%. A positive (+) sign attached to the category indicates a frequency toward the higher end of the probability, and a negative (-) sign indicates a frequency toward the lower end of the probability. The indicator category does not equate to the degrees of wetness tolerated by a given species.

Fen: a wetland area usually calcareous in nature, which has a supply of mineral rich ground water as the primary water source and has accumulated peat.

Flatwoods: a low lying woodland composed of hardwood tree species in the canopy which usually occupies the first terrace, not the primary floodplain.

Forested Wetland: a wetland with trees, in this area often adventive, but also including swamps and bottomland hardwood forests.

Genotype: a class or group of individuals sharing a specified genetic makeup.

Hydrologic Regime: the duration and timing of surface water characteristics, as well as, ground water fluctuations.

Impervious: a layer which does not allow water to pass through it.

Influorescence: an individual flower cluster, the arrangement of flowers on a plant.

Inundation: a condition in which water from any source temporarily or permanently covers a land surface.

Loam: a soil texture. Soil material that contains 7 to 27 percent clay, 28 to 50 percent silt, and less than 52 percent sand.

Marl: an earthy, unconsolidated deposit consisting chiefly of calcium carbonate mixed with clay or other impurities in varying proportions.

Marsh: wetland that is inundated much or all of the growing season and contains forbs and grasses but not many woody species. A periodically wet or continually flooded area where the surface is not deeply submerged’ covered dominantly with sedges, cattails, rushes, or other emergent plants.

Mesic: an area with well drained but moist soil for much of the growing season or year.

Mortality: of or pertaining to the death or death rate of a population.

OBL (Obligate): an indicator category for plants, estimating the probability of a given species to occur in wetlands at 99%. It does not estimate the degree of wetness tolerated by a given species.

Organic Soil: a soil that contains a high percentage (greater than 20 or 30%) of organic matter throughout the upper part of the soil profile.

Peat: a deposit of organic materials in a wet area where the material accumulates more quickly than it decomposes. The material is unconsolidated soil material consisting largely of un-decomposed or only slightly decomposed organic matter accumulated under conditions of excessive moisture and must contain indenfiable original fibers to correctly be called peat. Muck is the same material decomposed past recognition.

Perennial: a non-woody plant which lives more than two years, as distinguished from annuals and biennials.

Prairie: a level to hilly tract of land that has a dominance of grasses and forbs, has a scarcity of shrubs, and is almost treeless. The natural plant community consists of various mixes of native species.

Prairie Swale: a linear depression that is a least seasonally wet with slowly or non-flowing water and that is heavily vegetated with native grasses and forbs. Prairie swales serve as infiltration measures.

Propagule: a reproductive product of a parent plant. Propagules may be sexual in origin, such as, seeds, or asexual, such as, cuttings.

Pure Live Seed (PLS): the product of the percentage of germination plush the had seed and the percentage of pure live seed, divided by 100.

Rhizome: a horizontal or upright stem found underground or growing across the surface of the substrate, modified for reproduction or for food storage. It is particularly apparent in the rapid underground spread of many grasses.

Saturated: a soil layer with soil water pressure at zero or positive, It is not necessary for all soil pores to be filled with water for a soil to be saturated; some pores may have entrapped air or other gases. In the 1987 US Army Corps of Engineers wetland delineation manual, a soil is saturated when the capillary fringe occurs within 12 inches of the surface.

Scarification: the act of treating a hard coated seed by mechanical abrasion or with acid to facilitate water absorption and hasten germination .

Sedge Meadow: a native wetland plant community dominated by sedges.

Shrub-Scrub Wetland: an area dominated by woody vegetation less than 6 meters (20 feet) tall. Multiple stemmed species, immature tree species, and stunted species may all be found. In this geographic area the species are often adventive.

Stolon: a running stem or branch, aerial or along the surface of the substrate that can root at the nodes.

Stratification: cold treatment to break seed dormancy.

Substrate: the base or substance upon which a plant grows; or, a subsoil or layer underneath another layer.

Suckers: a shoot originating from the roots or lower part of the stem of a plant and usually developing rapidly.

Swale: a wide, shallow ditch or depression used to temporarily convey, store, and filter runoff. See Prairie Swale.

Swamp: an area saturated with water throughout much of the year but with the surface of the soil usually not deeply submerged; usually characterized by tree or shrub vegetation. A wetland that is saturated or inundated and contains woody plants. Often used in conjunction with a particular tree name, such as, cypress swamp.

Terrace: a level and ordinarily narrow plain usually with a steep front bordering a river or lake, but often above the primary floodplain in the landscape.

UPL (Upland): an indicator category for plants, estimating the probability of a given species to occur in uplands at 99%.

Watershed: all land and water within the confines of a drainage divide, or, the land which is tributary to a given river, lake, or stream.

Wet Meadow: a wetland that is inundated early in the season and dries out later in the season.

Wet Prairie: a prairie that is composed of grasses, sedges, and forbs and is situated in a moisture regime that is drier than a sedge meadow, but wetter than a mesic prairie. See Mesic and Prairie.

Glossary
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