Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-1 

GLOSSARY 

Abiotic - Not involving living organisms. 

Aboriginal Areas - This term is used today to describe the historic and prehistoric lands 

where a tribe (s) carried out food gathering or seasonal activities or traded with other Indian 

peoples. These areas are extensive. The range varies depending on the geographic terrain. 

FOR EXAMPLE: The Makah paddled whaling canoes in excess of 120 miles from the 

Washington Coast out to sea. The Nez Perce used to hunt buffalo in Eastern Montana. The 

Umatillas used to travel to the Oregon Coast and the Warm Springs peoples used to fish at 

Willamette Falls. (McConnell, 2003) 

Absorbed dose - In exposure assessment, the amount of a substance that penetrates an 

exposed organism's absorption barriers (e.g. skin, lung tissue, gastrointestinal tract) through 

physical or biological processes. Absorbed dose is synonymous with internal dose. 

Absorption - The process by which the chemical or other substance is able to pass through 

body membranes and enter an organism. In mammals and many other animals, the main 

routes by which toxic agents are absorbed are the gastrointestinal tract, lungs, and skin. 

ACGIH - American Conference of Governmental Industrial Hygienists. An organization of 

professionals in governmental agencies or educational institutions engaged in occupational 

safety and health programs. ACGIH develops and publishes recommended occupational 

exposure limits for chemicals (see TLV). (6500 Glenway Avenue, Bldg. D-7, Cincinnati, OH 

45211; (513) 661-7881. 

ACS - American Chemical Society. 

Active ingredient (a.i.) - In any pesticide product, the component (a chemical or biological 

substance) that kills or otherwise controls the target pests. Pesticides are regulated primarily 

on the basis of active ingredients. The remaining ingredients are called "inerts". 

Acute effect - An adverse effect on any living organism in which severe symptoms develop 

rapidly and often subside after the exposure stops. 

Acute exposure - A single exposure or multiple brief exposures occurring within a short time 

(e.g., 24 hours or less in humans). The classification of multiple brief exposures as “acute” is 

dependant on the life span of the organism. 

Acute lethality - The death of animals in a short period of time (typically up to14 days in 

mammals) after a single dose of a toxic substance. 

Acute toxicity - Any harmful effect produced in an organism through an acute exposure to 

one or more chemicals. 
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Glossary-2 

Adaptation - Changes in an organism's physiological structure or function or habits that 

allow it to survive in new surroundings. 

Adapted - “How well plants are physiologically suited for high survival, good growth, and 

resistance to pests and diseases in a particular environment” (Northern Region Native Plant 

Handbook, 1995). 

Additive effect - A situation in which the combined effects of exposure to two chemicals 

simultaneously is equal to the sum of the effect of exposure to each chemical given alone. 

The effect most commonly observed when an organism is exposed to two chemicals together 

is an additive effect. 

Adaptive management - A continuing process of action-based planning, monitoring, 

researching, evaluating, and adjusting with the objective of improving implementation and 

achieving the goals of the standards and guidelines (USDA, USDI 1994a). 

Adjuvant(s) - Chemicals that are added to pesticide products to enhance the toxicity of the 

active ingredient or to make the active ingredient easier to handle or mix. 

Administratively Withdrawn Areas - Areas removed from the suitable timber base through 

agency direction and land management plans. 

Adsorption - The tendency of one chemical to adhere to another material such as soil. 

Adverse-effect level (AEL) - Signs of toxicity that must be detected by invasive methods, 

external monitoring devices, or prolonged systematic observations. Symptoms that are not 

accompanied by readily observable signs of toxicity. Compare to “Frank-effect level”. 

Advisory - A non-regulatory document that communicates risk information to persons who 

may have to make risk management decisions. 

Aerobic - Life or processes that require, or are not destroyed by, the presence of oxygen. (see 

also, anaerobic). 

Affected Environment - Existing biological, physical, social, and economic conditions of an 

area subject to change, both directly and indirectly, as the result of a proposed human action. 

Agent - Any substance, force, radiation, organism, or influence that affects the body. The 

effects may be beneficial or injurious. 

Alien Species - “With respect to a particular ecosystem, any species, including its seeds, 

eggs, spores, or other biological material capable of propagating that species, that is not native 

to that ecosystem” (Executive Order 13122, 2/3/99). 
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Glossary-3 

Algae - Simple plants containing chlorophyll. Many are microscopic, but under conditions 

favorable for their growth they grow in colonies and produce mats and similar nuisance 

masses. 

Algal blooms - Sudden spurts of algal growth, which can affect water quality adversely and 

indicate potentially hazardous changes in local water chemistry. 

Alkali - Broadly, any compound having highly basic properties; i.e., one that readily ionizes 

in aqueous solution to yield OH anions, with a pH above 7. 

Alkaline phosphatase - An enzyme that occurs in various normal and malignant tissues. The 

activity of the enzyme in blood is useful in diagnosing many illnesses. 

Allelopathy - The suppression of growth of one plant species due to the release of toxic 

substances by another plant. 

Allometric - Pertaining to allometry, the study and measure of growth. In toxicology, the 

study of the relationship of body size to various processes that may impact how chemicals 

effect the organism or how the chemicals are transported within the organism. 

Allotted Lands - On Reservation - The Daws Act or General Allotment Act (1887), provided 

for dividing reservations into separate parcels, to encourage individual Indians in agricultural 

pursuits. Parcels were 160 acres for each family or 80 acres per single person. Any 

remaining acres over the population allocation were deemed “surplus” and opened up for 

settlement by non-Indians. Under the Act, Indian-held lands declined from 138 million acres 

in 1887 to 48 million acres in 1934. Of this remainder, 20 million acres are desert. The 

decline in Indian ownership was largely due to land being sold by Indian people in the interest 

of a short-term financial gain combined with a general disinterest in becoming a farmer. In 

1934, this act was superseded by the Indian Reorganization Act. (McConnell, 2003) 

Allotted Lands - Off Reservation - These lands were set aside to fulfill a need to maintain 

recognition of a specific group of Indian people. These are sometimes called Public Domain 

Allotments. Nearly all these acres are held in Trust status by the Interior Department, and 

administered by The Bureau of Indian Affairs. (McConnell, 2003) 

Alopecia - Loss of hair. 

Alluvial - Relating to clay, silt, sand, gravel, or similar detrital material deposited by flowing 

water. Alluvial deposits may occur after a heavy rain storm. 

Ambient - Usual or surrounding conditions. 

Amphibian - Any of a class of cold-blooded vertebrates (including frogs, toads, or 

salamanders) intermediate in many characteristics between fishes and reptiles and having 

gilled aquatic larvae and air-breathing adults. 
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Glossary-4 

Anadromous - Fish that spend their adult life in the sea but swim upriver to fresh water 

spawning grounds to reproduce. 

Anaerobic - Life or process that occurs in, or is not destroyed by, the absence of oxygen. 

Animal Unit Months - The amount of dry forage required by one animal unit for one month 

based on a forage allowance of 26 pounds per day (Society for Range Management 1989). 

Anions - Negatively charged ions in solution e.g., hydroxyl or OH– ion. 

Annual - A plant that endures for not more than a year. A plant which completes its entire 

life cycle from germinating seedling to seed production and death within a year. (Dayton, 

1950) 

Anoxia - Literally, "without oxygen". A deficiency of oxygen reaching the tissues of the 

body especially of such severity as to result in permanent damage. 

Antagonism - The interaction of two chemicals having an opposing, or neutralizing, effect on 

each other, or a chemical interaction that appears to have an opposing or neutralizing effect on 

a specific biological effect over what might otherwise be expected. 

Antibodies - Proteins produced in the body by immune system cells in response to antigens, 

and capable of combining with antigens. 

Antidote - A remedy to relieve, prevent, or counteract the effects of a poison. Eliminating the 

poison, neutralizing it, or absorbing it are effective. 

Antigens - A substance that causes production of antibodies when introduced into animal or 

human tissue. 

Anuria - Absence or defective excretion of urine. 

Apnea - A temporary stoppage of breathing. 

Aqueous - Describes a water-based solution or suspension. 

Aquifer - An underground geological formation, or group of formations, containing usable 

amounts of groundwater that can supply wells and springs. 

Arid - A terrestrial region lacking moisture, or a climate in which the rainfall is not sufficient 

to support the growth of most vegetation. 

Arthropods - Invertebrates belonging to the largest animal phylum (more than 800,000 

species) including crustaceans, insects, centipedes, and arachnids. Characterized by a 

segmented body, jointed appendages, and an exoskeleton composed of chitin (USDA, USDI 

1994a). 
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Glossary-5 

Assay - A kind of test (noun); to test (verb). 

Asymptomatic - Neither causing nor exhibiting symptoms. 

Ataxia - Loss of reflexes or muscular coordination. 

Atrophy - Reduction in size or function of tissue, organs, or the entire body caused by lack of 

use. 

ATSDR - Agency for Toxic Substances and Disease Registry; federal agency within the 

Public Health Service charged with carrying out the health-related analyses under CERCLA 

and SARA. 

Background level - In pollution, the level of pollutants commonly present in ambient media 

(air, water, soil). 

Bacteria - Microscopic living organisms that can aid in pollution control by metabolizing 

organic matter in soil, water, or other environmental media. Some bacteria can also cause 

human, animal and plant health problems. 

Basal application - In pesticides, the spreading of a chemical on stems or trunks of plants just 

above the soil line. 

Base - Substances that (usually) liberate OH anions when dissolved in water and weaken a 

strong acid. 

Benchmark - A dose associated with a defined effect level or designated as a no effect level. 

Benthic region - the bottom layer of a body of water. 

Benthos - the plants and animals that inhabit the bottom of a water body. 

Best management practice - A practice or combination of practices determined by a state or 

an agency to be the most effective and practical means (technological, economic, and 

institutional) of controlling point and nonpoint source pollutants at levels compatible with 

environmental quality. 

Bioaccumulation - The increase in concentration of a substance in living organisms as they 

take in contaminated air, water, or food because the substance is very slowly metabolized or 

excreted. 

Bioassay – (1) To measure the effect of a substance, factor, or condition using living 

organisms. (2) A test to determine the toxicity of an agent to an organism. 
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Glossary-6 

Bioconcentration - The accumulation of a chemical in tissues of a fish or other aquatic 

organism to levels greater than in the surrounding water. 

Bioconcentration factor (BCF) - The concentration of a compound in an aquatic organism 

divided by the concentration in the ambient water of the organism. 

Biodegradability - Susceptibility of a substance to decomposition by microorganisms; 

specifically, the rate at which compounds may be chemically broken down by bacteria and/or 

natural environmental factors. 

Biodiversity or biological diversity - “The diversity of living things (species) and of life 

patterns and processes (ecosystem structures and functions). Includes genetic diversity, 

ecosystem diversity, landscape and regional diversity, and biosphere diversity” (USDA Forest 

Service. “An Assessment of Ecosystem Components in the Interior Columbia Basin and 

Portions of the Klamath and Great Basins”, Vol. II, 1997). 

Biological Control - The use of nonnative agents including invertebrate parasites and 

predators (usually insects, mites, and nematodes), and plant pathogens to reduce populations 

of nonnative, invasive plants. 

Biological Magnification - The process whereby certain substances such as pesticides or 

heavy metals increase in concentration as they move up the food chain. 

Biologically sensitive - A term used to identify a group of individuals who, because of their 

developmental stage or some other biological condition, are more susceptible than the general 

population to a chemical or biological agent in the environment. 

Biomass - The amount of living matter. 

Biota or Biome - All living organisms of a region or system. 

BMPs - Best Management Practices. 

Body Burden - The amount of a chemical stored in the body at a given time, especially a 

potential toxin in the body as the result of exposure. 

Bradycardia - A decrease in normal heart rate. 

Broadcast application - In pesticides, to spread a chemical over an entire area. 

Bryophytes - Plants of the phylum Bryophyta, including mosses, liverworts, and hornworts; 

characterized by the lack of true roots, stems, and leaves (USDA, USDI 1994a). 

Buffer zone - A strip of untreated land that separates a waterway or other environmentally 

sensitive area from an area being treated with a pesticide. 
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Glossary-7 

Cancer potency parameter - A model-dependent measure of cancer potency (mg/kg/day)-1

over lifetime exposure. (Often expressed as a q1

*

 which is the upper 95 percent confidence 

limit of the first dose coefficient (q1) from the multistage model.) 

Candidate Species - Those plant and animal species that, in the opinion of the Fish and 

Wildlife Service (FWS) or NOAA Fisheries, may qualify for listing as endangered or 

threatened. The FWS recognizes two categories of candidates. Category 1 candidates are 

taxa for which the FWS has on file sufficient information to support proposals for listing. 

Category 2 candidates are taxa for which information available to the FWS indicates that 

proposing to list is possibly appropriate, but for which sufficient data are not currently 

available to support proposed rules. 

Capillary Fringe - The zone above the water table within which the soil or rock is saturated 

by water under less than atmospheric pressure. 

Carboxyhemoglobin - Hemoglobin in which the iron is bound to carbon monoxide(CO) 

instead of oxygen. 

Carcinogen - A chemical capable of inducing cancer. 

Carcinoma - A malignant tumor (cancer). 

Carrier - a non-pesticidal substance added to a commercial pesticide formulation to make it 

easier to handle or apply. 

CAS Registration number - An assigned number used to identify a chemical. CAS stands 

for Chemical Abstracts Service, an organization that indexes information published in 

Chemical Abstracts by the American Chemical Society and that provides index guides to help 

locate information about particular substances in the abstracts. Sequentially assigned CAS 

numbers identify specific chemicals. The numbers have no chemical significance. The CAS 

number is a concise, unique means of chemical identification. 

Categorical Exclusion - A class of actions which either individually or cumulatively would 

not have a significant effect on the human environment and therefore would not require 

preparation of an environmental assessment or environmental impact statement under the 

National Environmental Policy Act (NEPA). 

Cation - Positively charged ions in a solution. 
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Ceded Lands - This term was first used in the Treaty with the Wyandot, 1789. Since that 

time, many treaties referred to land cessions made by tribes to the United States. This term is 

used interchangeably with “treaty boundary” described elsewhere in the definitions. Most 

Federal agencies and Indian tribes prefer to use Ceded Lands when describing areas where a 

tribe did... “cede, relinquish, and convey to the U.S. all their right, title, and interest in the 

lands and country occupied by them”...at treaty signing or when reservations were 

established. Ceded land references are qualified by the legal definition of original tribal 

occupancy issued in 1978 by the U.S. Court of Claims. In effect: “only lands actually owned 

by a tribe can be ceded to the U.S.” (McConnell, 2003) 

Central nervous system (CNS) - The portion of the nervous system consisting of brain and 

spinal cord. 

CERCLA - Comprehensive Environmental Response, Compensation, and Liability Act. The 

initial legislation authorizing Superfund passed by Congress in December 1980. This law 

created a tax on the chemical and petroleum industries and provided broad Federal authority 

to respond directly to releases or threatened releases of hazardous substances that may 

endanger public health or the environment. 

Chlorophenoxy - A class of herbicides including 2,4-D (2,4-dichlorophenoxy acetic acid) 

and 2,4,5-TP (2,4,5-Trichlorophenoxy propionic acid). 

Chemical Control - The use naturally derived or synthetic chemicals called herbicides to 

eliminate or control the growth of invasive plants. 

Chlorophyll - A class of molecules found in plant cells that convert the energy of sunlight to 

food in the process known as photosynthesis. 

Cholinesterase - An enzyme found in animals that regulates nerve impulses. Cholinesterase 

inhibition is associated with a variety of acute symptoms such as nausea, vomiting, blurred 

vision, stomach cramps, and rapid heart rate, paralysis, convulsions, and death. 

Chlorosis - Yellowing or blanching of the leaves of plants due to loss of chlorophyll from 

causes other than lack of light. 

Chronic exposure - Exposures that extend over the average lifetime or for a significant 

fraction of the lifetime of the species (for a rat, chronic exposure is typically about 2 years). 

Chronic exposure studies are used to evaluate the carcinogenic potential of chemicals and 

other long-term health effects. 

Chronic RfD - An estimate of a lifetime daily exposure level for the human population, 

including sensitive subpopulations, that is likely to be without an appreciable risk of 

deleterious effects. Chronic RfDs are specifically developed to be protective for long-term 

exposure to a compound (7 years to lifetime). 
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Glossary-9 

Chronic toxicity - The ability of a substance or mixture of substances to cause harmful 

effects over an extended period, usually upon repeated or continuous exposure sometimes 

lasting for the entire life of the exposed organism. 

Code of Federal Regulations (CFR) - Document that codifies all rules of the executive 

departments and agencies of the federal government. It is divided into fifty volumes, known 

as titles. Title 40 of the CFR (referenced as 40 CFR) lists all environmental regulations, 

including regulations for EPA pesticide programs (40CFR Parts 150-189). 

Coliform - Microorganisms found in the intestinal tract of humans and animals. Their 

presence in water indicates fecal pollution and potentially dangerous bacterial contamination 

by disease-causing microorganisms. 

Confidential Business Information (CBI) - Information submitted to EPA by a pesticide 

registrant to fulfill requirements for pesticide registration that contains trade secrets or 

commercial or financial information that has been claimed as confidential by its source. EPA 

has special procedures for handling such information. 

Conifer Release – An intermediate treatment or cutting (not part of the sapling stage), 

designed to free a young stand of desirable trees, from competition by undesirable trees or 

competing vegetation. 

Congressionally Reserved Areas - Areas that require Congressional enactment for their 

establishment, such as National Parks, Wild and Scenic Rivers, National Recreation Areas, 

National Monuments, and Wilderness. Also referred to as Congressional Reserves (USDA, 

USDI 1994a). Includes similar areas established by Executive Order such as National 

Monuments. 

Conifer - An order of the Gymnospermae, comprising a wide range of trees and a few shrubs, 

mostly evergreens that bear cones and have needle-shaped or scalelike leaves; Conifer timber 

is commercially identified as softwood. 

Conjunctivitis - Inflammation of the conjunctive, the delicate membrane that lines the eyelid 

and covers the eyeball. 

Connected actions - Exposure to other chemical and biological agents in addition to exposure 

to a specific pesticide formulation in a field application to control pest organisms 

Contaminants - For chemicals, impurities present in a commercial grade chemical. For 

biological agents, other agents that may be present in a commercial product. 

Control - Means, as appropriate, eradicating, suppressing, reducing, or managing invasive 

species populations, preventing spread of invasive species from areas where they are present, 

and taking steps such as restoration of native species and habitats to reduce the effects of 

invasive species and to prevent further invasions (Executive Order 13122, 2/3/99). 
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Glossary-10 

Control - In toxicology or epidemiology studies, a population that is not exposed to the 

potentially toxic agent under study. 

Cornea - the transparent structure of the external layer of the eyeball. 

Creatine - An organic acid composed of nitrogen. It supplies the energy required for muscle 

contraction. 

Creatinine - The end product of the metabolism of creatine. It is found in muscle and blood 

and is excreted in the urine. 

Critical Effect - The first adverse effect that occurs as a dose rate increases. Designation is 

based on evaluation of overall database. 

Cultivar or variety - “A variety of plant produced through selective breeding by humans and 

maintained by cultivation” (King, 1997). 

Cultural Control - The establishment or maintenance of competitive vegetation, use of 

fertilizing, mulching, prescribed burning, or grazing animals to control or eliminate invasive 

plants. 

Cumulative exposures - Exposures resulting from one or more activities that are repeated 

over a period of time. 

Cumulative Impact - The impact on the environment that results from the incremental 

impact of the action when added to other past, present, and reasonably foreseeable future 

actions—regardless of what agency (federal or non-federal) or person undertakes such other 

actions. Cumulative impacts can result from individually minor, but collectively significant, 

actions taking place over a period of time (40 CFR 1508.7). 

Dams - A term used to designate females of some animals such as rats. 

Defoliant - a herbicide that removes leaves from growing plants. 

Degraded - Broken down or destroyed. 

Denitrification - Bacterial reduction of nitrite to gaseous nitrogen under anaerobic 

conditions. 

Dermal - Pertaining to the skin. 

Dermal Absorption/Penetration - Process by which a chemical penetratesthe skin and enters 

the body as an internal dose. 

Dermatitis - inflammation of the skin. 
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Glossary-11 

Detritivore - Animal that consumes decomposing organic particles, deriving nutrition 

primarily from microbes on the particles. 

Detritus - Loose fragments, particles, or grains formed by the disintegration of rocks or 

organic matter. 

Diatoms - organisms related to algae, having a brown pigmentation and silicate-based 

skeleton. 

Dislodgeable residues - The residue of a chemical or biological agent on foliage surface as a 

result of pesticide applications, which can be removed readily from the foliage by washing, 

rubbing or having some other form of direct contact with the treated vegetation. 

Dissociate - the process of ionization of a salt upon being dissolved in water. 

Disturbance - An effect of a planned human management activity, or unplanned native or 

exotic agent or event, that changes the state of a landscape element, landscape pattern, or 

regional composition” (USDA Forest Service. “An Assessment of Ecosystem Components in 

the Interior Columbia Basin and Portions of the Klamath and Great Basins”, Vol. II, 1997). 

Diversity - “The species richness of a community or area, though it provides a more useful 

measure of community characteristics when it is combined with an assessment of the relative 

abundance of species present” (Allaby, 1996). 

Dosage/Dose - 1. The actual quantity of a chemical administered to an organism or to which it 

is exposed. 2. The amount of a substance that reaches a specific tissue (e.g. the liver). 3. The 

amount of a substance available for interaction with metabolic processes after crossing the 

outer boundary of an organism. (See – absorbed dose, administered dose, applied dose, 

potential dose.) 

Dose Rate - In exposure assessment, dose per time unit (e.g. mg/day), sometimes also called 

dosage. 

Dose Response - Changes in toxicological responses of an individual (such as alterations in 

severity of symptoms) or populations (such as alterations in incidence) that are related to 

changes in the dose of any given substance. 

Dose Response Curve - Graphical representation of the relationship between the dose of a 

stressor and the biological response thereto. 

Dose-Response Assessment - A description of the relationship between the dose of a 

chemical and the incidence of occurrence or intensity of a specific biological response. 3. 

Evaluating the quantitative relationship between dose and toxicological responses. 

Dose-Response Relationship - The quantitative relationship between the amount of exposure 

to a substance and the extent of toxic injury or disease produced. 
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Glossary-12 

Drift - That portion of a sprayed chemical that is moved by wind off a target site. 

Dystrophic - Acidic, shallow bodies of water that contain much humus and/or other organic 

matter, many plants but few fish. 

EC50 - A concentration in air or in water that causes 50% inhibition of growth. 

EC100 - A concentration in air or water that causes complete inhibition of growth. 

Ecosystem - The complex of a community of organisms and its environments (Executive 

Order 13122, 2/3/99). 

Ecotype - “A locally adapted population of a widespread species. Such populations show 

minor changes of morphology and/or physiology, which are related to habitat and are 

genetically induced. Heavy metal-tolerant ecotypes of common grasses such as Agrostis 

tenuis are an example” (Allaby, 1996). 

Edema - an abnormal accumulation of clear, watery fluid in body tissue. 

Effects - Effects, impacts, and consequences are synonymous. Effects may be direct, indirect, 

or cumulative and may fall in one of these categories: aesthetic, historic, cultural, economic, 

social, health, or ecological (such as effects on natural resources and on the components, 

structures, and functioning of affected ecosystems) (USDA USDI 1994a). 

Electrochemical process - A newer manufacturing process for clopyralid. 

Embryo - an organism in the early stages of development before birth. In humans, the 

developing child is considered an embryo from conception to the end of the second month of 

pregnancy. 

Empirical - Refers to an observed, but not necessarily fully understood, relationship in 

contrast to a hypothesized or theoretical relationship. 

Endangered –Any species listed in the Federal Register as being in danger of extinction 

throughout all or a significant portion of its range. 

Endangered Species Act (ESA) - A law passed in 1973 to conserve species of wildlife and 

plants determined by the Director of the Fish and Wildlife Service or the NOAA Fisheries to 

be endangered or threatened with extinction in all or a significant portion of its range. Among 

other measures, ESA requires all federal agencies to conserve these species and consult with 

the Fish and Wildlife Service or NOAA Fisheries on federal actions that may affect these 

species or their designated critical habitat. 

Endemic - “A species or other taxonomic group that is restricted to a particular geographic 

region due to factors such as isolation or response to soil or climatic conditions” (Allaby, 

1996). Compare to “Indigenous” and “Native”. 
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Glossary-13 

Endocrine - referring to several glands in higher animals that secrete hormones. 

Environmental analysis - An analysis of alternative actions and their predictable short-term 

and long-term environmental effects, incorporating physical, biological, economic, and social 

considerations (USDA, USDI 1994a). 

Environmental Impact Statement (EIS) - A statement of the environmental effects of a 

proposed action and alternatives to it. It is required for major federal actions under Section 

102 of the National Environmental Policy Act (NEPA), and released to the public and other 

agencies for comment and review. It is a formal document that must follow the requirements 

of NEPA, the CEQ guidelines, and directives of the agency responsible for the project 

proposal. 

Environmental assessment - a written environmental analysis which is prepared pursuant to 

the National Environmental Policy Act to determine whether a federal action would 

significantly affect the environment and thus require preparation of a more detailed 

environmental impact statement. 

Environmental Equity/Justice - Equal protection from environmental hazards for 

individuals, groups, or communities regardless of race, ethnicity, or economic status. This 

applies to the development, implementation, and enforcement of environmental laws, 

regulations, and policies, and implies that no population of people should be forced to 

shoulder a disproportionate share of negative environmental impacts of pollution or 

environmental hazard due to a lack of political or economic strength levels. 

Environmental fate - The destiny of a chemical or biological pollutant after release into the 

environment. 

Environmental impact statement (EIS) - A document which identifies and analyzes, in 

detail, environmental impacts of a proposed action. As a tool for decision-making, the EIS 

describes positive and negative effects and lists alternatives for a proposed activity. Required 

by NEPA. 

Enzymes - Biological catalysts; proteins, produced by an organism itself, that enables the 

splitting (as in digestion) or fusion of other chemicals. 

Epidemiology study - A study of a human population or human populations. In toxicology, a 

study which examines the relationship of exposures to one or more potentially toxic agent to 

adverse health effects in human populations. 

Epilimnion - Upper waters of a thermally stratified lake subject to wind action. 

Estimated/Expected Environmental Concentration (EEC) - The estimated or expected 

pesticide concentration in an environmental media based on a particular set of assumptions 

and/or models. 
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Glossary-14 

Eutrophication - the slow aging process of a lake transforming into a marsh and eventually 

disappearing. During eutrophication the lake is choked by abundant plant life. 

Evapotranspiration - the loss of water from the soil both by evaporation and by transpiration 

from the plants growing in the soil. 

Exposure assessment - The process of estimating the amount of contact with a chemical or 

biological agent that an individual or a population of organisms will receive from a pesticide 

application conducted under specific, stated circumstances. 

Exotic - “Not native; introduced from elsewhere, but not completely naturalized” (Harris, 

1994). See “Alien Species”. 

Experimental Use Permit - Obtained by manufacturers for testing new, unregistered 

pesticides or new uses for registered pesticides whenever they conduct experimental field 

studies on 10 acres or more of land or one acre or more of water to support registration. 

Extirpate - To destroy completely; wipe out. 

Extrapolation - The use of a model to make estimates of values of a variable in an 

unobserved interval from values within an already observed interval. 

Fauna - The wildlife or animals of a specified region or time. 

Federal Campus - These are small parcels of land within a reservation for the use of the 

Bureau of Indian Affairs to build and maintain government housing, schools and 

administration buildings. (McConnell, 2003) 

Federal Recognition - Acknowledgment of an Indian tribe as a government entity that has a 

special relationship with the United States government. This relationship recognizes that 

Indian tribes receive some benefits or reserve some rights not available to other citizens; for 

example, health and education benefits from the trust relationship or off-reservation hunting 

and fishing rights related to treaties with tribal governments. 

The basic requirements for attaining Federal recognition include the following in the form of 

a petition to the Secretary of the Interior: 

1. A statement of facts regarding the continued identity of a group as “American 

Indian” or “Aboriginal” from historic times to the present. 

2. Evidence that a group exists as a community separate from other populations. 

3. Evidence it has maintained political influence over its members. 

4. A governing document such as a constitution. 

5. An enrollment list of all members. 

6. Not be involved in pending legislation regarding their status, or terminated by 

former Congressional action. (McConnell, 2003) 
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Glossary-15 

Federally Listed Species - Formally listed as a threatened or endangered species under the 

ESA. Designations are made by the FWS or NMFS. 

Fetal anomaly - An abnormal condition in a fetus, which is usually the result of a defect in 

development. 

Field capacity - The maximum amount of water that a soil can retain after excess water from 

saturated conditions has been drained by the force of gravity. 

FIFRA Pesticide Ingredient - An ingredient of a pesticide that must be registered with EPA 

under the Federal Insecticide, Fungicide, and Rodenticide Act. Products making pesticide 

claims must submit required information to EPA to register under FIFRA and may be subject 

to labeling and use requirements. 

Fire Management Plan - A strategic plan that defines a program to manage wildland and 

prescribed fires and documents the Fire Management Program in the approved land use plan. 

The plan is supplemented by operational plans such as preparedness plans, preplanned 

dispatch plans, prescribed fire plans, and prevention plans. (Interagency Implementation 

Guide, 1998) 

Flaming - A tool/technique for using fire to controlling invasive plants. Flaming is done with 

the use of propane torches. Flaming destroys cell structure in the plant, therefore reducing its 

energy towards growth. 

Flora - Plant life, especially all the plants found in a particular country, region, or time 

regarded as a group. Also, a systematic set of descriptions of all the plants of a particular 

place or time. 

Flowable - Pesticide formulations in which the active ingredients are finely ground insoluble 

solids suspended in a liquid. They are mixed with water for application. 

Foaming - Hot foam as a tool for controlling invasive plants has been tested by the Nature 

Conservancy and used by the BLM effectively on puncturevine and slender false brome. Hot 

foam is a non-chemical method. It is effective on seedlings and annuals and can be applied 

under weather conditions including wind and light rain.

Food chain - a hierarchical sequence of organisms, each of which feeds on the next, lower 

member of the sequence. 

Forage - Food for animals. In this document, term applies to both availability of plant 

material for wildlife and domestic livestock. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-16 

Forest Ecosystem Management Assessment Team (FEMAT) - An interagency, 

interdisciplinary team of scientists, economists, and sociologists led by Dr. Jack Ward 

Thomas and chartered to review proposals for management of federal forests within the range 

of the northern spotted owl. The team produced a report assessing ten options in detail, which 

were used as a basis for developing the Northwest Forest Plan. 

Formulation - A commercial preparation of a chemical including any inerts and/or 

contaminants. 

Fugitive Loss - When applied to dermal exposure, the chemical lost from the surface of the 

skin by means other than dermal absorption such as volatilization, washing, and loss of skin 

cells. 

Frank effects - Toxic effects that show obvious physical or behavioral symptoms/signs. 

Frank-effect level (FEL) - The dose or concentration of a chemical or biological agent that 

causes obvious physical or behavioral symptoms/signs of toxicity. 

Fungi - Molds, mildews, yeasts, mushrooms, and puffballs, a group of organisms that lack 

chlorophyll and therefore are not photosynthetic. They are usually nonmobile, filamentous, 

and multicellular. (Source: Carbon Dioxide Information Analysis Center, 1990) 

Game Fish - Species like trout, salmon, or bass, caught for sport. Many of them show more 

sensitivity to environmental change than non-game fish. 

Gavage - The placement of a toxic agent directly into the stomach of an animal, using a 

gastric tube. 

Genotoxic - Causing direct damage to genetic material. Associated with carcinogenicity. 

Geometric mean - The measure of an average value often applied to numbers for which a log 

normal distribution is assumed. 

Gestation - The period between conception and birth; in humans, the period known as 

pregnancy. 

GRAS - Generally Recognized As Safe. A phrase applied to food additives approved by the 

FDA. 

Gross Area - An area of land occupied by one or more invasive plant species. The area is 

defined by drawing a line around the general perimeter of the infestation, not the canopy 

cover of the plants. The gross area may contain significant parcels of land that are not 

occupied by the weed. (NRIS Standards) 

Groundwater - The supply of fresh water found beneath the Earth's surface, usually in 

aquifers, which is often supplies wells and springs. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-17 

Habitat - The place where a population (e.g., human, animal, plant, microorganism) lives and 

its surroundings, both living and non-living. 

Halftime or half-life - The time required for the concentration of the chemical to decrease by 

one-half. 

Hand Scalping for Planting - Hand scalping for planting is one of the forms of mechanical 

site preparation that removes competing vegetation and other damaging agents from the 

planting spot to increase the rate of survival of the planted material. 

Hazard quotient (HQ) - The ratio of the estimated level of exposure to a substance from a 

specific pesticide application to the RfD for that substance, or to some other index of 

acceptable exposure or toxicity. A HQ less than or equal to one is presumed to indicate an 

acceptably low level of risk for that specific application. 

Hazard identification - The process of identifying the array of potential effects that an agent 

may induce in an exposed of humans or other organisms. 

Health Advisory Level - A non-regulatory health-based reference level of chemical 

concentrations in drinking water at which there are no adverse health risks when ingested over 

various periods of time. Such levels are established by the Office of Drinking Water of the 

U.S. EPA for one day, 10 days, long-term and life-time exposure periods. 

Hematological - Pertaining to the blood. 

Hematology - One or more measurements regarding the state or quality of the blood. 

Hematuria - blood in the urine. 

Hemolytic anemia - A medical condition in which the number of red blood cells is decreased 

due to breakdown in the bloodstream. 

Henry's law constant - An index of the tendency of a compound to dissolve in and/or 

volatilize from aqueous solutions. 

Herbaceous - A plant that does not develop persistent woody tissue above the ground 

(annual, biennial, or perennial). Herbaceous vegetation includes grasses and grass-like 

vegetation, and broadleaved forbs. 

Herbicide - A chemical preparation designed to kill plants, especially weeds, or to otherwise 

inhibit their growth. 

Herbivore - an animal that feeds on plants. 

Heterotroph - Bacteria and other microorganisms that use organic matter synthesized by 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-18 

other organisms for energy and growth. 

Histology - The study of the structure of cells and tissues; usually involves microscopic 

examination of tissue slices. 

Histopathology - Signs of tissue damage that can be observed only by microscopic 

examination. 

Humus - Organic portion of the soil remaining after prolonged microbial decomposition. 

Hydrolysis - Decomposition or alteration of a chemical substance by water. 

Hydrogeology - The geology of ground water, with particular emphasis on the chemistry and 

movement of water. 

Hydroxylation - The addition of a hydrogen-oxygen or hydroxy (-OH) group to one of the 

rings. Hydroxylation increases the water solubility of most compounds and generally 

facilitates the elimination of the compound in the urine or bile. 

Hydrophilic - having an affinity for or being very soluble in water. 

Hydrophobic - lacking an affinity for water; is not wettable or soluble in water. 

Hydroxyl - the anion of water or OH-

, also present in all hydroxides. 

Hypolimnion - Bottom waters of a thermally stratified lake. The hypolimnion of a eutrophic 

lake is usually low or lacking in oxygen. 

Hypoxic - A condition of low oxygen concentration. 

In situ - The original location in the body or environment. 

In vivo - Occurring in the living organism. 

In vitro - Isolated from the living organism and artificially maintained, as in a test tube. 

Indian Country - A popular term today, which was derived from a reference to lands 

occupied by Indian peoples historically; then applied to reservations. It is commonly used 

now when referring to areas of concern to Indian tribes or even individuals, when conducting 

Indian business or protecting rights. (McConnell, 2003) 

Indian Land - Any land in collective tribal holding or ownership for which the Secretary of 

the Interior has a continuing trust responsibility to manage for the benefit of the respective 

tribe. Indian lands and reservations are not public lands and public land laws do not generally 

apply. In the past this term described certain parcels or areas where Indian lived and 

represented a smaller concept than Indian Territory. (McConnell, 2003) 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-19 

Indian Rights and Interest - Indian treaty and other rights or interests recognized by treaties, 

statutes, laws, executive orders, or other government action, or federal court decisions. 

(McConnell, 2003) 

Indian Territory - Unsurveyed lands that were recognized by the Federal government to be 

occupied or used by Indians. Prior to the United States Constitution, lands occupied or used 

by American Indians were referred to as Indian Territory. Historic documents dating back to 

the 16th century refer to these unsurveyed regions as a territory. (McConnell, 2003) 

Indian Tribe - Any American Indian or Alaska Native tribe, band, nation, pueblo, 

community, rancheria, colony, or group meeting the provisions of the Code of Federal 

Regulations Title 25, Section 83.7 (25 FR 83.7) or those recognized in statutes or treaties with 

the United States. (McConnell, 2003) 

Indigenous - “Born, growing, or produced naturally in a region or country; native” (Soil 

Conservation Society of America, 1982). 

Inerts - Anything other than the active ingredient in a pesticide product; not having pesticide 

properties. 

Infested Area - A contiguous area of land occupied by a single invasive plant species. An 

infested area of land is defined by drawing a line around the actual perimeter of the infestation 

as defined by the canopy cover of the plants, excluding areas not infested. Generally, the 

smallest area of infestation mapped will be 1/10th (0.10) of an acre or 0.04 hectares. (NRIS 

Standards). 

Ingestion - the taking in of a substance through the mouth for digestion. 

Internal Dose - In exposure assessment, the amount of a substance penetrating the absorption 

barriers (e.g. skin, lung tissue, gastrointestinal tract) of an organism through either physical or 

biological processes; synonymous with absorbed dose. 

Interpolation - The use of mathematical models within the range of observations 

Intraperitoneal - Injection into the abdominal cavity. 

Integrated Risk Information System (IRIS) - IRIS is an EPA data base containing verified 

RfDs and related information for numerous chemicals. Available at: 

http://www.epa.gov/iriswebp/iris/ index.html. 

Integrated Weed Management (IWM) - An interdisciplinary weed management approach 

for selecting methods for preventing, containing, and controlling noxious weeds in 

coordination with other resource management activities to achieve optimum management 

goals and objectives (FSM 2080.5). 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-20 

Interdisciplinary team (IDT) - A group of individuals with varying areas of specialty 

assembled to solve a problem or perform a task. The team is assembled out of recognition 

that no one scientific discipline is sufficiently broad enough to adequately analyze the 

problem and propose action. 

Introduced Species - An alien or exotic species that has been intentionally or nonintentionally released into an area as a result of human activity. “Introduced (agricultural 

crops may fit the definition as well as ‘native’ or ‘introduced’ wildland species) or exotic 

species whose genetic material originally evolved and developed under different 

environmental conditions than those of the area in which it was introduced, often in 

geographically and ecologically distant locations” (Brown, 1997). See also “Noxious Weed” 

and “Exotic”. 

Introduction - “The intentional or unintentional escape, release, dissemination, or placement 

of a species into an ecosystem as a result of human activity” (Executive Order 13122, 2/3/99). 

Invasive Plant Species - An alien plant species whose introduction does or is likely to cause 

economic or environmental harm or harm to human health (Executive Order 13122, 2/3/99). 

Iritis - Inflammation of the iris, the circular pigmented membrane behind the cornea, 

perforated by the pupil. 

Irreversible effect - Effect characterized by the inability of the body to partially or fully 

repair injury caused by a toxic agent. 

Irritant - Non-corrosive material that causes a reversible inflammatory effect on living tissue 

by chemical action at the site of contact as a function of concentration or duration of exposure 

Issue - A point, matter, or question of public discussion or interest to be addressed or decided 

through the planning process. 

LC50 (lethal concentration50) - A calculated concentration of a chemical in air or water to 

which exposure for a specific length of time is expected to cause death in 50 percent of a 

defined experimental animal population. 

LD50 (lethal dose50) - The dose of a chemical calculated to cause death in 50 percent of a 

defined experimental animal population over a specified observation period. The observation 

period is typically 14 days. 

Label - All printed material attached to or part of the pesticide container (W). 

Land allocation - Commitment of a given area of land or a resource to one or more specific 

uses (such as campgrounds or Wilderness). In the Northwest Forest Plan, one of the seven 

allocations of Congressionally Withdrawn Areas, Late-Successional Reserves, Adaptive 

Management Areas, Managed Late-Successional Areas, Administratively Withdrawn Areas, 

Riparian Reserves, or Matrix. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-21 

Land management - Intentional process of planning, organizing, programming, 

coordinating, directing, and controlling land use actions. 

Latency - Time from the first exposure to a chemical until the appearance of a toxic effect. 

Late-successional forests - Forest stands consisting of trees, structural attributes, supporting 

biological communities, and processes associated with old-growth and/or mature forests 

(USDA, USDI 1994a). Forest seral stages that include mature and old-growth age classes 

(USDA, USDI 1994a). Age is not necessarily a defining characteristic but has been used as a 

proxy or indicator in some usages. Minimum ages are typically 80 to 130 years, more or less, 

depending on the site quality, species, rate of stand development, and other factors. 

Leachate - Water that collects chemicals as it trickles through soil or other porous media 

containing the chemicals. 

Leaching - the process by which chemicals on or in soil or other porous media are dissolved 

and carried away by water, or are moved into a lower layer of soil. 

Level of Concern (LOC) - The concentration in media or some other estimate of exposure 

above which there may be effects. 

Lethargy - sluggish behavior. Less than typical activity. 

Lichens - Complex thallophytic plants comprised of an alga and a fungus growing in 

symbiotic association on a solid surface (such as a rock). 

Lipophilic - having an affinity for oil or fat. 

Littoral zone - 1). That portion of a body of fresh water extending from the shoreline 

lakeward to the limit of occupancy of rooted plants. 2). The strip of land along the shoreline 

between the high and low water levels. 

Local - “”Pertaining to, characteristic of, or restricted to a particular place or particular 

places” (Barnhart, 1970). 

Local Native - “A population of native plant species which originated, i.e., grew from seeds 

or cuttings, from genetically local sources. The geographic and elevational boundaries that 

define a species’ genetically local source are determined by plant movement guidelines” (Mt. 

Baker-Snoqualmie NF Native Plant Handbook, 1994). 

Lowest-observed-adverse-effect level (LOAEL) - The lowest dose of a chemical in a study, 

or group of studies, that produces statistically or biologically significant increases in 

frequency or severity of adverse effects between the exposed and control populations. 

Lymphatic – Pertaining to lymph, a lymph vessel, or a lymph node. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-22 

Lymph - A clear water fluid containing white blood cells. Lymph circulates throughout the 

lymphatic system, removing bacteria and certain proteins from body tissue. It also is 

responsible for transporting fat from the small intestine and supplying mature lymphocytes to 

the blood. 

Macrophyte - terrestrial or aquatic plant that is large enough to be seen without the aid of a 

microscope. 

Macroscopic organisms - Organisms big enough to be seen by the eye without the aid of a 

microscope. 

Malignant - Cancerous. 

Manual Control - The use of any non-mechanized approach to control or eliminate invasive 

plants (i.e. hand-pulling, grubbing). 

Margin of safety (MOS) - The ratio between an effect or no effect level in an animal and the 

estimated human dose. 

Margin of Exposure (MOE) - The ratio of the no-observed adverse-effect-level to the 

estimated exposure dose. 

Marsh - A type of wetland that does not accumulate appreciable peat deposits and is 

dominated by herbaceous vegetation. Marshes may be either fresh or saltwater, tidal or nontidal. 

Material safety data sheet (MSDS) - a compilation of information required under the OSHA 

Communication Standard on the identity of hazardous chemicals, health and physical hazards, 

exposure limits, and precautions. 

Mature forest - A subset of Late-Successional forests. Mature forests are characterized by 

the onset of slowed height growth, crown expansion, heavier limbs, gaps, some mortality in 

larger trees, and appearance of more shade-tolerant species or additional crown layers. In 

Douglas-fir west of the Cascades, this stage typically begins between 80 and 130 years, 

depending on site conditions and stand history (adapted from USDA, USDI 1994b, pp. B-2 

and B-3). 

Maximally (or Most) Exposed Individual - The person with the highest exposure in a given 

population. 

Maximum Acceptable Toxic Concentration - For a given ecological effects test, the range 

(or geometric mean) between the No Observable Adverse Effect Level and the Lowest 

Observable Adverse Effects Level. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-23 

Maximum Tolerated Dose - The maximum dose that an animal species can tolerate for a 

major portion of its lifetime without significant impairment or toxic effect other than 

carcinogenicity. 

Mechanical Control - The use of any mechanized approach to control or eliminate invasive 

plants (i.e. mowing, weed whipping). 

Mechanical Site Preparation – Mechanical site preparation involves physical modification 

of the site by hand or machinery to prepare a seedbed or planting spot for the reforestation of 

the site. 

Media - Specific environments such as air, water, soil, animal or plant matter. 

Mesotrophic - Reservoirs and lakes which contain moderate quantities of nutrients and are 

moderately productive in terms of aquatic animal and plant life. 

Methemoglobin - a soluble, brown, crystalline blood pigment that differs from hemoglobin in 

that it contains ferric iron and is unable to combine reversibly with molecular oxygen. 

Methemoglobinemia - the presence of methemoglobin in the bloodstream caused by the 

reaction of materials with the hemoglobin in red blood cells that reduces their oxygencarrying capacity. 

Metabolism - The sum of the chemical reactions occurring within a cell or a whole organism; 

includes the energy-releasing breakdown of molecules (catabolism) and the synthesis of new 

molecules (anabolism). 

Metabolite - A compound formed as a result of the metabolism or biochemical change of 

another compound. 

Metameter - Literally, the unit of measure. Used in dose-response or exposure assessments 

to describe the most relevant way of expressing dose, exposure or response. 

Microcosm - A small but representative system analogous to a larger system in composition, 

development, or configuration. 

Microorganisms - A generic term for all organisms consisting only of a single cell, such as 

bacteria, viruses, protozoans and some fungi. 

Microsomal - Pertaining to portions of cell preparations commonly associated with enzymes 

involved in the metabolism of xenobiotics. 

Mineralization - The release of inorganic chemicals from organic matter in the process of 

aerobic or anaerobic decay – i.e., typically used as an expression of complete degradation. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-24 

Minimal risk level (MRL) - A route-specific (oral, dermal, or inhalation) and durationspecific estimate of an exposure level that is not likely to be associated with adverse effects in 

the general population, including sensitive subgroups. 

Minimum tool - Use of a weed treatment alternative that would accomplish management 

objectives and have the least impact on resources. 

Mitigation measures - Modifications of actions taken to: (1) avoid impacts by not taking a 

certain action or parts of an action; (2) minimize impacts by limiting the degree or magnitude 

of the action and its implementation; (3) rectify impacts by repairing, rehabilitating, or 

restoring the affected environment; (4) reduce or eliminate impacts over time by preservation 

and maintenance operations during the life of the action; or, (5) compensate for impacts by 

replacing or providing substitute resources or environments (USDA, USDI 1994a). 

Mitochondria - A component in a cell that is involved in the conversion of food to stored 

chemical energy. 

Modeling - Use of mathematical equations to simulate and predict real events and processes. 

Molecule - The smallest division of a compound that still retains or exhibits all the properties 

of the substance. 

Mollusks - Invertebrate animals (such as slugs, snails, clams, or squids) that have a soft 

unsegmented body usually enclosed in a calcareous shell; representatives found on National 

Forest System land include snails, slugs, and clams. 

Monitoring - A process of collecting information to evaluate if objectives and anticipated or 

assumed results of a management plan are being realized or if implementation is proceeding 

as planned (USDA, USDI 1994a). 

Morbidity - Rate of disease, injury or illness. 

Most sensitive effect - The adverse effect which is observed at the lowest dose level, given 

the available data. This is an important concept in risk assessment because, by definition, if 

the most sensitive effect is prevented, no other effects will develop. Thus, RfDs are normally 

based on doses at which the most sensitive effect is not likely to develop. 

Motile - Capable of self-propelled movement. A term that is sometimes used to distinguish 

between certain types of organisms found in water. 

Mucous membrane - a thin soft pliable layer of tissue that secretes mucous; i.e., nose, 

mouth, stomach, intestine, bronchial tubes, and urinary tract. 

Multiple chemical sensitivity - A syndrome that affects individual persons who are 

extremely sensitive to chemicals at extremely low levels of exposure. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-25 

Mutagenicity - The ability of a substance to cause genetic damage (that is damage to DNA or 

RNA). 

Mutagen - a substance that causes mutations. 

Mutation - a change in the genetic material in a cell. Mutations can lead to adverse clinical 

effects. 

Narcosis - stupor or unconsciousness often produced by exposure to organic chemicals. 

National Environmental Policy Act (NEPA) - An Act passed in 1969 to declare a National 

policy that encourages productive and enjoyable harmony between humankind and the 

environment, promotes efforts that prevent or eliminate damage to the environment and 

biosphere, stimulates the health and welfare of humanity, enriches the understanding of the 

ecological systems and natural resources important to the nation, and establishes a Council on 

Environmental Quality (USDA, USDI 1994a). 

National Forest Management Act (NFMA) - A law passed in 1976 as an amendment to the 

Forest and Rangeland Renewable Resources Planning Act, requiring preparation of Forest 

Plans and the preparation of regulations to guide that development (USDA, USDI 1994a). 

National Marine Fisheries Service (NMFS) - The federal agency that is the listing authority 

for marine mammals and anadromous fish under the ESA. 

National Pollutant Discharge Elimination System (NPDES) - A provision of the Clean 

Water Act which prohibits discharge of pollutants into waters of the United States unless a 

special permit is issued by EPA, a state, or, where delegated, a tribal government on an Indian 

reservation. 

Native Species - With respect to a particular ecosystem, a species that, other than as a result 

of an introduction, historically occurred or currently occurs in that ecosystem (Executive 

Order 13122, 2/3/99). 

Naturalized - “Applied to a species that originally was imported from another country but 

that now behaves like a native in that it maintains itself without further human intervention 

and has invaded native populations” (Allaby, 1996). 

Necrosis - Death of plant or animal cells or tissues. In plants, necrosis can discolor stems or 

leaves or kill a plant entirely. In animals, necrosis can be minimal (focal or diffuse) or 

massive – i.e., resulting in loss of organ function that can sometimes lead to death of the 

organism. 

Nematodes - Roundworms, some of which are pathogenic for plants and sometimes animals. 

Neurotoxin - a material that affects the nerve cells and may produce muscular, emotional, 

behavioral abnormalities, impaired or abnormal motion and other physiologic changes. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-26 

Neutral - in pH terms, 7; neither acid nor basic. 

Nitrification - the process whereby ammonia in soil or water is oxidized to nitrite and then to 

nitrate by bacterial or chemical reactions. 

Nitrogen fixation - The biological or chemical process by which elemental nitrogen, from the 

air, is converted to organic or available nitrogen. 

NLAA see Not Likely to Adversely Affect)

Non-local Native - “This term has two meanings: 1) a population of a native plant species 

which does not occur naturally in the local ecosystem and/or 2) plant material of a 

native species that does not originate from genetically local sources. (Northern 

Region Native Plant Handbook, 1995). 

Non-essential - defined as not needed for future management 

Non-target - Any plant or animal that is not the intended organism to be controlled by a 

pesticide treatment. 

No-observed-adverse-effect level (NOAEL) - exposure level at which there are no 

statistically or biological significant differences in the frequency or severity of any adverse 

effect in the exposed or control populations. 

No-Observed-Effect-Level (NOEL) - exposure level at which there are no statistically or 

biological significant differences in the frequency or severity of any effect in the exposed or 

control populations. 

Normal distribution - A standard pattern used in statistics to describe one way in which 

variability occurs in a population. 

Northwest Forest Plan - Coordinated ecosystem management direction incorporated into 

land and resource management plans for lands administered by the BLM and the Forest 

Service within the range of the northern spotted owl. In April 1993, President Clinton 

directed his cabinet to craft a balanced, comprehensive, and long-term policy for management 

of over 24 million acres of public land within the range of the northern spotted owl. A Forest 

Ecosystem Management Assessment Team (FEMAT) was chartered to develop a series of 

options. These options were modified in response to public comment and additional analysis 

and then analyzed in a Final Supplemental Environmental Impact Statement (USDA, USDI 

1994a). A Record of Decision was signed on April 13, 1994, by the Secretaries of the 

Department of Agriculture and the Department of Interior to adopt Amendments to Forest 

Service and Bureau of Land Management Planning Documents Within the Range of the 

Northern Spotted Owl (USDA, USDI 1994b). The Record of Decision, including the 

Standards and Guidelines for Management of Habitat for Late-Successional and Old-Growth 

Forest Related Species Within the Range of the Northern Spotted Owl is referred to as the 

“Northwest Forest Plan.” The Northwest Forest Plan is not a “plan” in the agency planning 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-27 

regulations sense; the term instead refers collectively to the 1994 amendment to existing 

agency land and resource management plans or to the specific standards and guidelines for 

Late-Successional species incorporated into subsequent land and resource management plans. 

Not Likely to Adversely Affect (NLAA) - determinations are applied to those species that 

had very little habitat on National Forests in Region Six, were not in habitats susceptible to 

invasive plants, or were known to tolerate herbicide treatments without effects. 

Noxious Weed - “Any living stage (including but not limited to, seeds and reproductive 

parts) of any parasitic or other plant of a kind, or subdivision of a kind, which is of foreign 

origin, is new to or not widely prevalent in the United States, and can directly or indirectly 

injure crops, other useful plants, livestock, or poultry or other interests of agriculture, 

including irrigation, or navigation or the fish and wildlife resources of the United States or the 

public health” (Public Law 93-629, January 3, 1975, Federal Noxious Weed Act of 1974). 

NPDES see National Pollutant Discharge Elimination System

Octanol-water partition coefficient (Kow) - The equilibrium ratio of the concentrations of a 

chemical in n-octanol and water, in dilute solution. 

Ocular - Pertaining to the eye. 

OECD Guidelines - Testing guidelines prepared by the Organization of Economic and 

Cooperative Development of the United Nations. They assist in preparation of protocols for 

studies of toxicology, environmental fate, etc. 

Off-Highway Vehicle Recreation – In this document, the term off-highway vehicle (OHV) 

refers to vehicles used for off-highway pursuits and may include 3 and 4 wheelers, 

motorcycles, dune buggies, 4x4 vehicles, and other motorized vehicles. 

Old-growth forest - An ecosystem distinguished by old trees and related structural attributes. 

Old growth encompasses the later stages of stand development that typically differ from 

earlier stages in a variety of characteristics which may include tree size, accumulations of 

large dead woody material, number of canopy layers, species, composition, and ecosystem 

function. More specific parameters applicable to various species are available in the 1993 

Interim Old Growth Definitions (USDA Forest Service Region 6). The Northwest Forest Plan 

SEIS and FEMAT describe old-growth forest as a forest stand usually at least 180 to 220 

years old with moderate-to-high canopy closure; a multi-layered, multi-species canopy 

dominated by large overstory trees; high incidence of large trees, some with broken tops and 

other indications of old and decaying wood (decadence); numerous large snags; and heavy 

accumulations of wood, including large logs on the ground (USDA, USDI 1994a). 

Oligotrophic - a term applied to describe deep clear lakes with low nutrient supplies. They 

contain little organic matter and have a high dissolved oxygen level. 

Oliguria - scanty or low volume of urine. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-28 

Oral Toxicity - Ability of a pesticide to cause injury when ingested. 

Organic matter - carbonaceous material contained in soil, plants or animal matter. 

Parenteral - Any form of injection into the body. 

Partition - In chemistry, the process by which a compound or mixture moves between two or 

more media. 

Partition Coefficient - The ratio of concentrations of a chemical in two different media at 

equilibrium – e.g, octanol/water. 

Pathogen - A living organism, typically a bacteria or virus, that causes adverse effects in 

another organism. 

Pathway - In metabolism, a sequence of metabolic reactions. 

Percolation - downward flow or filtering of water through pores or spaces in rock or soil. 

Perennial - A plant species having a life span of more than 2 years. 

Periphyton - Microscopic plants and animals that are firmly attached to solid surfaces under 

water such as rocks, logs, pilings and other structures. 

Permeability - For dermal exposures, permeability refers to the degree to which a chemical in 

contact with the skin is able to penetrate the skin. 

Persistence - refers to the length of time a compound, once introduced into the environment, 

stays there. 

Personal Protective Equipment (PPE) - Clothing and equipment worn by pesticide mixers, 

loaders and applicators and re-entry workers, hazmat emergency responders, workers cleaning 

up Superfund sites, et. al., which is worn to reduce their exposure to potentially hazardous 

chemicals and other pollutants. 

Pest - An insect, rodent, nematode, fungus, weed or other form of terrestrial or aquatic plant 

or animal life that is classified as undesirable because it is injurious to health or the 

environment. 

Pesticide - Any substance used for controlling, preventing, destroying, repelling, or 

mitigating any pest. Includes fungicides, herbicides, fumigants, insecticides, nematicides, 

rodenticides, desiccants, defoliants, plant growth regulators, and so forth. (W, modified). 

Pesticide tolerance - the amount of pesticide residue allowed by law to remain in or on a 

harvested crop. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-29 

pH - The negative log of the hydrogen ion concentration. A high pH (>7) is alkaline or basic 

and a low pH (<7) is acidic. 

Pharmacokinetics - The quantitative study of the absorption, distribution, metabolism, and 

excretion of chemicals by an organism. 

pKa - The negative log of the hydrogen ion concentration or pH at which 50% of a weak acid 

is dissociated. 

Photosynthesis - the manufacture by plants of carbohydrates and oxygen from carbon dioxide 

and water in the presence of chlorophyll, using sunlight as an energy source. 

Physiographic province - A geographic area having a similar set of biophysical 

characteristics and processes due to effects of climate and geology that result in patterns of 

soils and broad-scale plant communities. Habitat patterns, wildlife distributions, and 

historical land use patterns may differ significantly from those of adjacent provinces (USDA, 

USDI 1994a) (See Figure 1 in the standards and guidelines). 

Phytoplankton - that portion of the plankton community – i.e., organisms in water – 

comprised of tiny plants, e.g., algae, diatoms. 

Phytotoxic - something that harms plants. 

Plankton - small aquatic organisms with limited powers of locomotion, carried by water 

currents from place to place. 

Planning area - All of the lands within a federal agency’s management boundary addressed 

in land management plans (USDA, USDI 1994a). 

Plant - Any of various photosynthetic, eukaryotic (meaning an organism with cells having a 

distinct nucleus), multicellular organisms of the kingdom Plantae characteristically producing 

embryos, containing chloroplasts, having cellulose cell walls, and lacking the power of 

locomotion. (For purposes of this EIS, the term “plant” does not include “mushrooms” and 

“fungi”) 

Population - “A group of individuals of the same species in an area” (Wilson and Hipkins, 

1999). 

Population at Risk - A population subgroup that is more likely to be exposed to a chemical, 

or is more sensitive to the chemical, than is the general population. 

Porosity - Degree to which soil, gravel, sediment, or rock is permeated with pores or cavities 

through which water or air can move. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-30 

Portal-of-Entry Effect - A local effect produced in the tissue or organ of first contact 

between a toxicant and the biological system. 

Potable Water - Water that is considered safe for drinking and cooking. 

Potentiation - The ability of one chemical to increase an effect of another chemical on an 

organism. 

Precautionary Principle - When information about potential risks is incomplete, basing 

decisions about the best ways to manage or reduce risks on avoiding unnecessary or uncertain 

health risks instead of on avoiding unnecessary economic expenditures. 

Precommercial Thinning - A critical treatment made to reduce stand density of trees 

primarily to improve growth or enhance forest health to improve growth or enhance forest 

health and is associated with sapling and pole size stands. 

Predation - The act or practice of capturing another creature (prey) as a food source. 

Pre-disturbance surveys - See “Surveys Prior to Habitat-Disturbing Activities.” 

Prescribed Fire - Any fire ignited by management actions to meet specific objectives. A 

written approved fire plan must exist, and NEPA requirements must be met, prior to ignition. 

This term replaces management ignited prescribed fire. (Interagency Implementation Guide, 

1998). 

Prevention - To detect and ameliorate conditions that cause or favor the introduction, 

establishment, or spread of invasive plants. 

Procaryote - A single-celled organism in which the nucleus has no limiting membrane 

Programmatic - Of having, advocating, or following a plan, policy, or program, as in a 

Programmatic EIS. 

Propagule - A structure (cutting, seed, or spore) that allows a plant to reproduce. 

Proposed species - Any plant or animal species that is proposed by the Fish and Wildlife 

Service or NOAA Fisheries in a Federal Register notice to be listed as threatened or 

endangered. 

Proposive surveys - One type of landscape-scale or strategic survey, proposive surveys are 

focused searches conducted where taxa experts anticipate finding the target species. They are 

used to find sites of the rarest species, i.e. those that may not be picked up in random plots. 

Also referred to as purposive surveys. 

Potential Vegetation Type – The term potential vegetation type (PVT) is used to represent 

the combination of species that could occupy the site in the absence of disturbance. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-31 

Protozoa - Single-celled, microorganisms without cell walls containing visibly evident nuclei 

and organelles. Most protozoa are free-living although many are parasitic. 

Prospective - In epidemiology, a type of study in which the populations are identified prior to 

exposure to a presumptive toxic agent, in contrast to a retrospective study. 

Protinated - an acid (A-

) that is combined with a proton (H+) and has a neutral charge (AH). 

The dissociated form of the acid has a negative charge (A-

) e.g.: Sulfuric acid: H2SO4Ù2H+

+ SO4-

Prudent industrial hygiene - precautionary measures taken to protect human health when 

exposed to potentially harmful materials. This includes keeping hands, other parts of the 

body, work clothing, and equipment free of a material's residue, as well as not eating, 

drinking, applying makeup, or using toilet facilities where the material is in use. 

Pruning - Pruning is the removal of limbs on the lower portion of a tree. The primary 

objectives of pruning are to increase the clear wood volume of a tree when harvested and for 

purposes of disease control. Other objectives may include wildlife habitat improvement, 

aesthetics, and reduction of fuel loads. 

Pulmonary edema - fluid in the lungs. 

Rare - A species is considered to be rare when: there are a low number of extant known sites 

with low numbers of individuals present at each site and populations are not well-distributed 

within its natural range. "Low" numbers and "not well distributed" are relative terms that 

must be considered in the context of other criteria such as distribution of habitat, fecundity, 

and so forth. See complete list of criteria under "Relative Rarity" in the standards and 

guidelines. 

Receiving waters - All distinct bodies of water that receive runoff or wastewater discharges, 

such as streams, rivers, ponds, lakes, and estuaries. 

Receptor - Ecological entity exposed to a stressor. 

Reclamation - The process of mitigating physical or chemical environmental conditions 

perceived to be limiting to land management objectives and attempting to alter or lessen the 

effect of environmental damage through whatever means are available” (Brown, 1997). 

Record of Decision - A document separate from, but associated with, an environmental 

impact statement that: (1) states the management decision; (2) states the reason for that 

decision, (3) identifies all alternatives including the environmentally preferable and selected 

alternatives; and (4) states whether all practicable measures to avoid environmental harm 

from the selected alternative have been adopted, and if not, why not (USDA, USDI 1994a). 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-32 

Reference Dose (RfD) - The RfD is a numerical estimate of a daily exposure to the human 

population, including sensitive subgroups such as children, that is not likely to cause harmful 

effects during a lifetime. RfDs are generally used for health effects that are thought to have a 

threshold or minimum dose for producing effects.

Registered Pesticides - Pesticide products which have been approved for the uses listed on 

the label (W). 

Rehabilitate - “Producing an alternative ecosystem that is consistent with existing land uses 

but that has a different structure and function from the original system [i.e. ski areas]” 

(National Academy of Sciences, 1974). 

Registration - Formal licensing with EPA of a new pesticide before it can be sold or 

distributed. Under the Federal Insecticide, Fungicide, and Rodenticide Act, EPA is 

responsible for registration (pre-market licensing) of pesticides on the basis of data 

demonstrating no unreasonable adverse effects on human health or the environment when 

applied according to approved label directions. 

Release - A treatment done to free desirable trees from competition with less desirable 

vegetation. 

Relative weight - The weight of an organ, such as the liver or kidney, divided by the total 

body weight of the animal. 

Reproductive effects - Adverse effects on the reproductive system that may result from 

exposure to a chemical or biological agent. The toxicity of the agents may be directed to the 

reproductive organs or the related endocrine system. Toxic effects may be manifested as 

alterations in sexual behavior, fertility, pregnancy outcomes, or modifications in other 

functions dependent on the integrity of this system. 

Reregistration - the reevaluation and relicensing by EPA of existing pesticides that were 

originally registered prior to current scientific and regulatory standards. EPA re-registers 

pesticides through its Registration Standards Program. 

Resorption - Removal by absorption. Often used in describing the unsuccessful development 

and subsequent removal of post-implantation embryos. 

Restoration - “[Ecological restoration] is the process of assisting the recovery and 

management of ecological integrity. Ecological integrity includes a critical range of 

variability in biodiversity, ecological processes and structures, regional and historical context, 

and sustainable cultural practices” (Society of Ecological Restoration, 2000). 

Retrospective - Looking behind. In epidemiology, a type of study in which the populations 

are identified after exposure to a presumptive toxic agent, in contrast to a prospective study. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-33 

Revegetation - “The re-establishment of plants on a site (does not imply native or nonnative; does not imply that the site can ever support any other types of plants or species and is 

not at all concerned with how the site ‘functions’ as an ecosystem)”. (Northern Region 

Native Plant Handbook, 1995). 

RfD - A daily dose which is not anticipated to cause any adverse effects in a human 

population over a lifetime of exposure. These values are derived by the U.S. EPA. 

Riparian Area - A geographic area containing an aquatic ecosystem and adjacent upland 

areas that directly affect it (Northwest Forest Plan). 

Riparian Reserves - Areas along live and intermittent streams, wetlands, ponds, lakes, and 

unstable and potentially unstable areas where riparian-dependent resources receive primary 

emphasis. Riparian Reserves are important to the terrestrial ecosystem as well, serving as 

dispersal habitat for certain terrestrial species (USDA, USDI 1994a). 

Risk Assessment - An analytic process that is firmly based on scientific considerations, but 

also requires judgments to be made when the available information is incomplete. These 

judgments inevitably draw on both scientific and policy considerations. (VMT). 

Risk - the chance of an adverse or undesirable effect. 

Risk assessment - the qualitative and quantitative evaluation performed in an effort to 

estimate the risk posed to human health and/or the environment by the presence or potential 

presence and/or use of specific chemical or biological agents. 

Risk communication - the exchange of information about health or environmental risks 

between risk assessors, risk managers, the general public, news media, interest groups, etc. 

Risk management - the process of evaluating potential alternative regulatory and non 

regulatory responses to risk and selecting among them. The selection process necessarily 

requires the consideration of legal, economic and social factors. 

Rough Fish - Fish not prized for sport or eating, such as gar and suckers. Most are more 

tolerant of changing environmental conditions than are game or food species. 

Road prism - This is the horizontal template of a road that includes the road running surface, 

cutslope, fillslope, and ditch. 

Route of exposure - The way in which a chemical or biological agent enters the body. Most 

typical routes include oral (eating or drinking), dermal (contact of the agent with the skin), 

ocular (eye contact) and inhalation. 
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Glossary-34 

SARA - Superfund Amendments and Reauthorization Act (1986); federal law reauthorizing 

and expanding the jurisdiction of CERCLA. Signed into law October 17, 1986. Title III of 

SARA is known as the Emergency Planning and Community Right- to-Know Act of 1986. It 

is a revision and extension of CERCLA. 

Saturated zone - a subsurface area in which all pores and cracks are filled with water under 

pressure equal to or greater than that of the atmosphere. 

Scientific notation - The method of expressing quantities as the product of a number between 

1 and 10 multiplied by 10 raised to some power. For example, in scientific notation, 1 kg = 

1,000g would be expressed as 1 kg = 1 x 103

 g and 1 mg = 0.001 would be expressed as 1 mg 

= 1 x 10-3

Seed Transfer Zone - “Geographic subdivisions within the Region, encompassing areas of 

similar environmental conditions" (USDA Forest Service, 1993). 

Sensitive species – Species identified by the Regional Forester for which population 

variability is a concern, as evidenced by significant current or predicted downward trend in 

population numbers or density; or significant current or predicted downward trends in habitat 

capability that would reduce a species existing distribution (FSM 2670).. 

Sensitive subgroup - Subpopulations that are much more sensitive than the general public to 

certain agents in the environment. 

Sensitization - A condition in which one is or becomes excessively or abnormally susceptible 

or reactive to an agent through repeated exposure. 

Signal Words - The words used on a pesticide label to indicate a level of toxicity specified by 

EPA: Danger, Warning, or Caution. 

Silviculture - Management of forest land for diverse purposes through manipulation of the 

density, structure and species composition of the trees thereon. 

Sink – As in “population sink”; portions of a species’ geographic range where death rates 

exceed birth rates. 

Site preparation - The removal of competing vegetation and debris to enhance a site for 

planting, and survival and growth of seedlings, or to enhance germination of natural seed (on 

site). 

Special Review - Formerly known as Rebuttable Presumption Against Registration (RPAR), 

this is the regulatory process through which EPA reviews existing pesticides suspected of 

posing unreasonable risks to human health, non-target organisms, or the environment. Special 

review requires an intensive risk/benefit analysis with opportunity for public comment. If 

EPA determines that risks outweigh social and economic benefits, EPA may initiate 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-35 

regulatory actions ranging from label revisions and use-restriction to cancellation or 

suspended registration. 

Species - “A group of organisms all of which have a high degree of physical and genetic 

similarity, generally interbreed only among themselves, and show persistent differences from 

members of allied groups of organisms” (Executive Order 13122, 2/3/99). 

Species-to-species extrapolation - A method using exposure data on one species (usually an 

experimental animal) to estimate the effects of exposure in another species (usually humans or 

wildlife). 

Stokes' law - an formula for calculating the rate of fall of particles through a air or a fluid 

based on densities, viscosity, and particle size. 

Standards and guidelines - The rules and limits governing actions, as well as the principles 

specifying the environmental conditions or levels to be achieved and maintained (USDA, 

USDI 1994a). 

Subchronic exposure - An exposure duration that can last for different periods of time (5 to 

90 days), with 90 days being the most common test duration for mammals. The subchronic 

study is usually performed in two species (rat and dog) by the route of intended use or 

exposure. 

Subchronic toxicity - the ability of one or more substances to cause effects over periods from 

about 90 days but substantially less than the lifetime of the exposed organism. Subchronic 

toxicity only applies to relatively long-lived organisms such as mammals. 

Subcutaneous - beneath the skin. 

Submerged Aquatic Vegetation - Vegetation that lives at or below the water surface; an 

important habitat for young fish and other aquatic organisms. 

Substrate - With reference to enzymes, the chemical that the enzyme acts upon. 

Succession - “The development of biotic communities following disturbances that produce 

an earlier successional community” (USDA Forest Service. “An Assessment of Ecosystem 

Components in the Interior Columbia Basin and Portions of the Klamath and Great Basins”, 

Vol. II, 1997). 

Surface water - all water naturally open to the atmosphere (rivers, lakes, reservoirs, streams, 

impoundments, seas, estuaries, etc.) and all springs, wells, or other collectors which are 

directly influenced by surface water. 

Surfactant - a surface active agent; usually an organic compound whose molecules contain a 

hydrophilic group at one end and a lipophilic group at the other. Promotes solubility of a 

chemical, or lathering, or reduces surface tension of a solution. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-36 

Survey and Manage - Mitigation measure adopted as a set of standards and guidelines within 

the Northwest Forest Plan Record of Decision and replaced with standards and guidelines in 

2001 (Record of Decision) intended to mitigate impacts of land management efforts on those 

species that are closely associated with Late-Successional or old-growth forests whose longterm persistence is a concern. This mitigation measure applies to all land allocations and 

requires land managers to take certain actions relative to species of plants and animals, 

particularly some amphibians, bryophytes, lichens, mollusks, vascular plants, fungi, and 

arthropods, which are rare or about which little is known. These actions include: (1) manage 

known sites; (2) survey prior to habitat-disturbing activities; and, (3) conduct extensive and 

general regional (strategic) surveys. 

Surveys Prior to Habitat Disturbing Activities - Surveys conducted to determine if the 

species is present at a site proposed for habitat disturbing activities. Includes “practical 

surveys” and “equivalent-effort surveys”. 

Synergistic effect - situation in which the combined effects of exposure to two chemicals 

simultaneously is much greater than the sum of the effect of exposure to each chemical given 

alone. 

Systemic effects - Effects observed at sites distant from the entry point of a chemical due to 

its absorption and distribution in the body. 

Systemic toxicity - Effects that require absorption and distribution of a toxic agent to a site 

distant from its entry point at which point effects are produced. Systemic effects are the 

opposite of local effects. 

Tachycardia -excessively rapid heartbeat. 

Tachypnea -increased rate of respiration. 

Take - To kill or capture a species covered by the ESA. 

Teratogenic -Causing structural defects that affect the development of an organism; causing 

birth defects. 

Teratology -The study of malformations induced during development of young animals 

including humans from conception to birth. 

Threatened species - Plant or animal species likely to become endangered throughout all or a 

significant portion of its range within the foreseeable future. A plant or animal identified and 

defined in accordance with the 1973 Endangered Species Act and published in the Federal 

Register (USDA, USDI 1994a). 

Threshold - The maximum dose or concentration level of a chemical or biological agent that 

will not cause an effect in the organism. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-37 

Threshold Limit Value (TLV) - The concentration of an airborne substance to which an 

average person can be repeatedly exposed without adverse effects. TLVs may be expressed in 

three ways – (1) TLV-TWA--Time weighted average, based on an allowable exposure 

averaged over a normal 8-hour workday or 40-hour work- week; (2) TLV-STEL--Short-term 

exposure limit or maximum concentration for a brief specified period of time, depending on a 

specific chemical (TWA must still be met); and (3) TLV-C--Ceiling Exposure Limit or 

maximum exposure concentration not to be exceeded under any circumstances. (TWA must 

still be met.) 

Thymus - small gland that is the site of T-cell production. The gland is composed largely of 

lymphatic tissue and is situated behind the breastbone. The gland plays an important role in 

the human immune system. 

Time-weighted average (TWA) - The average air concentration of material during a given 

period of time. 

Tolerances - Permissible residue levels for pesticides in raw agricultural produce and 

processed foods. Whenever a pesticide is registered for use on a food or a feed crop, a 

tolerance (or exemption from the tolerance requirement) must be established. EPA 

establishes the tolerance levels, which are enforced by the Food and Drug Administration and 

the Department of Agriculture. 

Tool of Last Resort – A tool that will be used only if all other methods for managing 

invasive plants are ineffective or too expensive. 

Toxicity - The inherent ability of an agent to affect living organisms adversely. As defined 

by U.S. EPA, toxicity is “...the degree to which a substance or mixture of substances can harm 

humans or animals. 

Toxicology - The study of the nature, effects, and detection of poisons in living organisms. 

Also, substances that are otherwise harmless but prove toxic under particular conditions. The 

basic assumption of toxicology is that there is a relationship among the dose (amount), the 

concentration at the affected site, and the resulting effects. 

Traditional - The beliefs, acts, practices, objects and/or sites for the perpetuation of an Indian 

culture originating from or historically located at a specific area. This may include cultural 

practices that are so interrelated with spiritual activities that they cannot be separated from the 

land location. (McConnell, 2003) 

Transpiration - The process by which living plants release water vapor to the atmosphere. 

Treated Area - An infested area where weeds have been treated or retreated by an acceptable 

method for the specific objective of controlling their spread or reducing their density. (NRIS 

Standards). 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-38 

Treaty - A legally binding agreement between two or more sovereign governments. With 

respect to American Indian tribes, a treaty is a document negotiated and concluded by a 

representative of the President of the United States and ratified by 2/3 majority vote of the 

U.S. Senate. (McConnell, 2003) 

Treaty Boundaries - A modern term that applies to lands described within the treaty 

document, usually outlining an area of land that is ceded to the U.S. (McConnell, 2003) 

Treaty Resources - Resources upon which the exercise of the treaty right depends. An 

exhaustive list does not exist, because Indian tribes maintain confidentiality for names of 

medicines or spiritual plants and other natural resources. (McConnell, 2003) 

Treaty rights - Tribal rights or interests reserved in treaties, by Indian Tribes for the use and 

benefit of their members. The uses include such activities as described in the respective treaty 

document. Only Congress may abolish or modify treaties or treaty rights. (McConnell, 2003) 

Tribal Self-Governance - First stated in modern terms by former President Nixon in 1970, as 

“Self Determination”, this refers to the ability of Indian Tribal governments to make decisions 

that affect either the general tribal population or tribal assets. A modern U.S. Indian policy 

that reinstates the independent decision making process of Indian tribal entities that had 

existed before European contact. In 1982, Congress passed new authorities whereby Indian 

Tribes could sign a Compact directly with the Secretary of the Interior without involving the 

Bureau of Indian Affairs in the delivery of federal services. Using appropriations formerly 

sent through the Bureau of Indian Affairs, Indian Tribes can now prioritize their own 

expenditures of federal funds. (McConnell, 2003) 

Trust allotment - Federal land set aside for the exclusive use of an Indian, who is the allottee. 

The Federal government retains land ownership, many allotments are outside the bounds of 

Indian reservations, called public domain allotments. (McConnell, 2003) 

Trust Land - Any land in collective tribal holding or individual ownership for which the 

Secretary of the Interior has a continuing trust responsibility to manage in a manner to benefit 

the respective tribe or individual. The most common example is forested acres on a 

reservation. Some Trust lands were set aside as compensation for claims made against the 

Government; most of which are off-reservation. (McConnell, 2003) 

Trust Resources - Indian owned assets, held in trust status by the Secretary of the Interior for 

the exclusive use and benefit of tribes or their members. Such as property, tribal timber or 

other resources usually found within the bounds of Indian reservations. (McConnell, 2003) 

Trust Responsibility - This term has never been defined by the U.S. Congress, any President 

or Cabinet official. Generally it is a set of principles and concepts outlining the 

responsibilities of the United States Government to act as the trustee of Indian people and 

Indian owned assets. The United States government, through the President has certain 

responsibilities to protect Indian property and rights, Indian lands, and resources. The trust 

responsibility may involve a fiduciary obligation in which the President, through the Secretary 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-39 

of the Interior acts as the trustee of Indian assets. Fulfilling or redeeming a trust 

responsibility, can best be reflected or demonstrated as a matter of action; a stream that was 

protected, a site that was maintained in tact, a property right that has been left unaffected by a 

federal action. The writing of an environmental document is not an example of fulfillment of 

a trust duty. (McConnell, 2003) 

Uncertainty factor (UF) - A factor used in operationally deriving the RfD and similar values 

from experimental data such as NOAEL or LOAEL. UFs are intended to account for (1) the 

variation in sensitivity among members of the human population; (2) the uncertainty in 

extrapolating animal data to humans; (3) the uncertainty in extrapolating from data obtained 

in a study that is less than lifetime exposure; and (4) the uncertainty in using LOAEL data 

rather than NOAEL data. Usually each of these factors is set equal to 10. 

Unsaturated - In terms of molecular structure, a carbon atom in a hydrocarbon molecule that 

shares a double bond with another carbon atom. 

Unsaturated or Vadose Zone - The area above the water table where the soil pores are not 

fully saturated, although some water may be present. 

U.S. Fish and Wildlife Service (USDI FWS) - The federal agency that is the listing authority 

for species other than marine mammals and anadromous fish under the ESA. 

Vehicle - An inert ingredient (usually a liquid) used as a medium for suspending or dissolving 

the pesticidal active ingredient. Commonly used vehicles include water, acetone, and corn 

oil. 

Viability - Ability of a wildlife or plant population to maintain sufficient size to persist over 

time in spite of normal fluctuations in numbers, usually expressed as a probability of 

maintaining a specific population for a specified period (USDA, USDI 1994a). 

Viable Population - A wildlife or plant population that contains an adequate number of 

reproductive individuals appropriately distributed on the planning area to ensure the long-term 

existence of the species (USDA, USDI 1994a). 

Volatile - Referring to compounds or substances that have a tendency to vaporize. A material 

that will evaporate quickly. 

Weak acid - an acid that is not substantially dissociated at a neutral pH. Many herbicides as 

well as many naturally occurring organic chemicals are weak acids. Mammals have well 

developed systems to excrete weak acids. 

Weed - “A plant growing where man does not want it to grow” (Daubenmire, 1978). 

Well distributed - Distribution sufficient to permit normal biological function and species 

interactions, considering life history characteristics of the species and the habitats for which it 

is specifically adapted. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-40 

Wetlands - an area that is regularly saturated by surface or ground water and subsequently is 

characterized by a prevalence of vegetation that is adapted for life in saturated soil conditions. 

Examples include swamps, bogs, fens, marshes, and estuaries. 

Wilderness - Areas designated by Congressional action under the 1964 Wilderness Act. 

Wilderness is defined as undeveloped federal land retaining its primeval character and 

influence without permanent improvements or human habitation. Wilderness areas are 

protected and managed to preserve their natural conditions, which generally appear to have 

been affected primarily by the forces of nature with the imprint of human activity 

substantially unnoticeable; have outstanding opportunities for solitude or for a primitive and 

confined type of recreation; include at least 5,000 acres or are of sufficient size to make 

practical their preservation, enjoyment, and use in an unimpaired condition; and may contain 

features of scientific, educational, scenic, or historical value as well as ecological and 

geologic interest (USDA, USDI 1994a). 

Wildfire - An unwanted wildland fire. This term is included to give continuing credence to 

the to the historic fire prevention products. This is NOT a separate type of fire. (Interagency 

Implementation Guide, 1998). 

Wildland Fire - Any nonstructure fire, other than prescribed fire, that occurs in the wildland. 

This term encompasses fires previously called both wildfires and prescribed natural fires. 

(Interagency Implementation Guide, 1998). 

Wildland Fire Suppression - An appropriate management response to wildland fire that 

results in curtailment of fire spread and eliminates all identified threats from the particular 

fire. All wildland fire suppression activities provide for firefighter and public safety as the 

highest consideration, but minimize loss of resource values, economic expenditures, and/or 

the use of critical firefighting resources. (Interagency Implementation Guide, 1998). 

Wildland Fire Use - The management of naturally ignited wildland fires to accomplish 

specifically prestated resource management objectives in predefined geographic areas 

outlined in fire management plans (FMP). Operational management is described in wildland 

fire implementation plans (WFIP). Wildland fire use is not to be confused with “fire use”, 

which is defined as, the combination of wildland fire use and prescribed fire application to 

meet resource objectives. (Interagency Implementation Guide, 1998). 

Xenobiotic - term for non-naturally occurring or man-made substances found in the 

environment. 

Zooplankton – Small (often microscopic) aquatic animals and nonphotosynthetic protists 

suspended or weakly swimming in water. Zooplankton provides an important food source for 

many aquatic animals. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-41 

Glossary Bibliography 

A large number of environmental glossaries are available on the Internet. The current glossary is 

based on previous glossaries in various Forest Service/SERA Risk Assessments as well as three 

glossaries available publicly on the internet: The University of Washington, Forest Soils Home 

Page (http://soilslab.cfr.washington.edu/S-7/ envglossary.html), the U.S. EPA 

(http://www.epa.gov/OCEPAterms), and the National Safety Council: 

(http://www.nsc.org/ehc/glossary.htm). The entries taken from these three sites are only those 

terms that may be relevant to and helpful in the review of the Forest Service risk assessments. 

For a more extensive series of definitions, the above links should be consulted directly. 

Following is a list of bibliographic references in addition to those referenced above. 

Allaby, M., ed., 1996. The Concise Oxford Dictionary of Botany, Oxford University Press, Oxford, Great Britain. 

Barnhart, C.L. 1970. The American College Dictionary. Random House, New York. 

Brown, R.W.; Amacher, M. C. 1997. “Selecting plant species for ecological restoration: a perspective for land 

managers: proceedings, 1997 Society for Ecological Restoration annual meeting; 1997 November 12-15; 

Ft. Lauderdale, FL Proc RMRS-P-8, Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky 

Mountain Research Station. 

Daubenmire, R., 1978. Plant Geography, Academic Press, INC., New York, NY. 

Dayton, W.A. 1950. Glossary of botanical terms used in range research, Revised Edition. Miscellaneous Publication 

110, 41 pp. Washington, DC: U.S. Department of Agriculture. 

Federal Native Plant Conservation Committee, 1994. Office of the Federal Environmental Executive, Federal 

Register, pp. 40837-41. 

Harris, J.G.; Harris M.W. 1994. Plant Identification Terminology. Spring Lake Publishing, Payson, UT. 

King, R.C.; Stansfield, W.D. 1997. A Dictionary of Genetics. Oxford University Press, New York, NY. 

Northern Region Native Plant Handbook, 1995. USDA Forest Service, Northern Region. 

McConnell, L. 2003. Tribal Relations, USDA Forest Service, Pacific Northwest Region. 

Potash, L.; Aubry, C.; Busse, B.; Hamilton, W.; Ketcheson, G.; Henderson, J.; Mace, R. 1994. Mt. BakerSnoqualmie NF Native Plant Handbook. R6-MBS-003-94. USDA Department of Agriculture, Forest 

Service, Pacific Northwest Region. 

Society for Ecological Restoration International Science & Policy Working Group. 2002. The SER Primer on 

Ecological Restoration. www.ser.org. This citation can be abbreviated in text as: (SER 2002). 

Soil Conservation Society of America, 1982. Soil Conservation Glossary, Soil Conservation Society of America, 

Ankeny, IA. 

USDA Forest Service, 1993. Forest Service Handbook 2409.26f, Seed Handbook, Region 2, USDA Forest Service, 

Lakewood, CO, 200: 2. 
Preventing and Managing Invasive Plants Final Environmental Impact Statement April 2005 

Glossary-42 

USDA Forest Service. 1997. An Assessment of Ecosystem Components in the Interior Columbia Basin and Portions 

of the Klamath and Great Basins, Vol. II. 

U.S. Department of Agriculture. 1974. Federal Noxious Weed Act. In 

http://bluegoose.arw.r9.fws.gov/FICMNEWFiles/FederalNoxiousWeedAct.html. 

Wilson and Hipkins. Genetics vocabulary. Handout for the “Short Course in Genetic Issues Using Native Plants in 

Revegetation”, Lakewood, CO, Sept. 1999. 

Wilson, E.O. 1988. The current state of biological diversity. p. 3-18 in E.O. Wilson and F.M. Peter, eds. 

Biodiversity. N.