Glossary

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Annual: A plant that lives for one year or one growing season. It may self seed and produce another annual the following year.

Beneficial Landscaping: Using different landscaping techniques to achieve a variety of benefits (e.g., decrease of maintenance costs, reduction of stormwater runoff, beautification of the landscape, preservation of endangered species).

Berm: A mound of earth formed to control the flow of surface water.

Biennial: A plant that grows from seed and produces leafy growth the first year. In the second year, it produces flowers, sets seed and dies.

Biodiversity: A measurement of the number of species and the variety of life and its processes in an area.

Bioretention: A water quality practice that utilizes landscaping and soils to treat stormwater runoff by collecting it in shallow depressions and filtering it through a planting soil media.

BMP: (Best Management Practice) A state-of-the-art method for achieving a desired benefit, such as infiltration or improved water quality.

Buffer: A vegetated strip immediately adjacent to a water body. The primary function of buffers is to protect the receiving water from sediment and pollutants derived from upstream areas. Ancillary benefits may include infiltration of rainfall and habitat enhancement. Forested riparian buffers are one example of a best management practice related to the use of buffers.

Buffer Strip: A management area closest to a sensitive environmental site (e.g., wetland, waterbody, etc.) in which human activities are prohibited or limited in order to minimize the negative impacts from adjacent land uses (like erosion, filter runoff pollutants, disturbances of wildlife) affecting the sensitive environmental site.

Clean Water Act: The Clean Water Act is an act originally passed in 1972 by the U.S. Congress to control water pollution.

Clustered Development: Concentration of development on only a portion of a site, allowing sensitive areas to be protected with no loss in the number of lots and maintaining the overall density of the site.

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Ecosystem: A community of plants and animals interacting with each other and the physical/chemical environment.

Emergent: Pertaining to aquatic plants which have some portion of the plant extended out of the water.

Evapotranspiration: The combined processes of evaporation from the water or soil surface and transpiration of water by plants.

Exotic Species: A non-native plant or animal introduced from another geographic area.

Extended Detention (ED) Pond: Temporarily detains part of stormwater runoff for up to 24 hours after a storm by using a fixed orifice. ED ponds normally are "dry" between storm events and do not have permanent standing water. An enhanced ED pond is designed to prevent clogging and resuspension. It provides flexibility in achieving target detention times. It may be equipped with plunge pools near the inlet, a micropool at the outlet, and may have an adjustable reverse-sloped pipe at the ED control device.

Forest: Plant communities which exist along floodplains or on the eastern side of rivers where they were protected from fires. They are dominated by trees that are intolerant of fire and can grow in poorly drained soils, although bur oak trees can be a part of this community. In Northeastern Illinois, the word "forest" is often used interchangeably with "woodland" or "woods," as in the "Big Woods."

Fen: A type of wet meadow with highly alkaline soil. Vegetation is primarily composed of herbaceous species, encircled by zones of plants of increasing height and woodiness.

Filter Strip: A vegetated boundary characterized by uniform mild slopes. Filter strips may be forested or vegetated turf. Filter strips located adjacent to waterbodies are called buffers.

Floodplain: Areas that are flooded periodically (usually annually) by the lateral overflow of rivers. In hydrology, the entire area that is flooded at a recurrence interval of 100 years.

Forb: Any herbaceous plant that is not a grass.

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Greenway: A greenway is a corridor of open land that provides one or more of the following benefits: (1) protection and management of natural and cultural resources; (2) provision of recreational opportunities; and (3) enhancement of the quality of life and the aesthetic appeal of neighborhoods and communities.

Groundwater Recharge: Increasing the amount of groundwater in storage via percolating rainwater.

Habitat: The physical, chemical, and biological environment in which organism live.

Herbaceous Plant: Any plant that is not woody.

Impervious Surface: Those surfaces in the landscape that can not infiltrate rainfall, such as rooftops, pavement, sidewalks, driveways and compacted earth.

Infiltration: The downward movement of water from the surface of the land to subsoil.

Invasive Plant: A plant that establishes easily and spreads aggressively into new areas and environments, often with detrimental effects on native plant species.

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Landscaping: The design of outdoor space to serve the needs of people by planting, altering the contours of the ground and/or components like walkways, paths and patios..

Mesic: Soil condition that is medium-wet.

Native Landscaping: Landscaping only by using native plants.

Native Species: A plant or animal that originally occurred in an area.

National Pollutant Discharge Elimination System (NPDES): The national program for issuing, modifying, revoking and reissuing, terminating, monitoring and enforcing permits, and imposing and enforcing pretreatment requirements.

Natural Landscaping: Landscaping in a way that tries to capture the character and spirit of nature in a designed landscape by arranging plants in a community context similar to their arrangement in nature. May be planted exclusively with native plants or incorporate some small percent of exotics.

Nonpoint Source Pollution: Originating from diffuse areas (land surface or atmosphere) having no well-defined source.

Oak Savanna: The transitional community between prairie and forest, sustained by fires and characterized by scattered, open-grown oak and hickory trees and grasses and forbs which flourish in partly shady conditions. These savannas were often called "oak openings" by the pioneers. Definitions of density of trees vary widely, from a few scattered trees to an almost closed canopy.

Ordinance: A municipally adopted law or regulation.

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Perennial Plant: A plant which lives for more than two years.

Point-source Pollution: Source of pollution can be pinpointed, such as a drain or chimney stack.

Pollutant: Solid waste, incinerator residue, pet waste, sewage, garbage, sediment, chemical wastes.

Prairie: A plant community dominated by a diversity of perennial, herbaceous plants growing between a majority of grasses, and forming a dry flammable turf in autumn. Prairie communities are categorized by soil conditions into dry (sandy or shallow hilltop soils), mesic (medium wetness) and wet prairies (poorly drained soils). Often characterized by very deep rooted plants. Prairie vegetation also consists of shallow-rooted species, some with widely spreading root systems.

Prescribed Burn: Controlled application of fire to naturally occurring vegetative fuels under specified environmental conditions and following appropriate precautionary measures. The fire is confined to a predetermined area and accomplish the planned land management objectives.

Runoff: That part of the precipitation that appears in surface water bodies after traveling across land.

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Setback: Area between intensive development (i.e., structures) and a protected area (e.g., waterbody or wetland).

Storm Water: Storm water runoff, snow melt runoff, and surface runoff and drainage.

Stormwater Detention Basin: A waterbody designed to etain stormwater runoff and reduce flooding.

Total Maximum Daily Load (TMDL): The amount of pollutant, or property of a pollutant, from point, nonpoint, and natural sources, that may be discharged to a water quality-limited receiving water.

Weed: Any undesirable or troublesome plant, especially one that grows profusely where it is not wanted.