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Vegetation classification hierarchy (Hunter and Paysen 1986) |
Formation ↓ |
Subformation ↓ |
Series ↓ |
Association |
composite fire interval: Number
of years between fires that scarred one or more trees within a given area
(Dieterich 1980). Often indicates the number of years
between fires that scarred at least one tree in the area (e.g.,
Heyerdahl and others 2001),
but may describe number of years between fires that scarred a certain proportion of trees
in the area (for example, Stephens
and others 2003). This criterion (single tree, two or more,
10% or more, etc.) must be specified. The Composite Fire Interval is estimated from a
pool of trees within an area, and is intended to account for the likelihood that not
every tree will be scarred by every fire that occurs in the area
(Patton 2007).
See also fire interval and
point fire interval.
consocies:
Part of an association lacking one or more of its dominant species
(Lincoln and others 1998).
constancy:
The relative consistency of occurrence of a species.
1) May be expressed as proportion of samples in which a species occurs, in which case it is similar to
frequency
(Helms 1998).
2) May be described as one of several classes representing dominance or cover (for example,
Atzet and others 1996).
FEIS uses frequency if that is clearly the author's meaning. Otherwise, FEIS uses constancy.
cool-season:
A plant that makes most of its growth during winter and spring
and sets seed in late spring or early summer
(Frost and Ruyle 1993).
Also see warm-season.
cooperative breeding:
A breeding system where older siblings or adults other than the parents help rear the current-year's brood
(Elphick and others 2001, Wilson 2000).
coppice sprout:
Any stem arising from an adventitious or dormant bud at or near the base of
a woody plant that has been cut back
(Ford-Robertson 1971).
corm:
A short, solid, vertical underground stem with thin papery leaves
(Harris and Harris 2001).
corpusculum:
The gland connecting the 2 waxy pollen grain masses in milkweeds (Asclepiadaceae)
(Harris and Harris 2001).
cotyledon:
An embroynic seed leaf; there are characteristically 1 for monocots and 2 for dicots
(Allaby 1992).
cover:
The proportion of ground covered by the aerial parts of individuals of a species,
usually expressed as a percentage. Total cover for all species on a site can exceed 100%. However,
top-cover,
the proportion of ground for which a species provides the uppermost cover, cannot exceed 100%
(Grieg-Smith 1983).
Mueller-Dombois and Ellenberg (1974)
consider basal area a special kind of "cover," but FEIS does not usually use COVER in this way.
crepuscular:
Active during twilight hours of dusk and dawn
(Lincoln and others 1998).
crown class:
Measure of stand structure classifying trees within a stand as dominant (crowns
rise through or above general canopy and receive full light from above and partial
light from the sides), codominant (crowns in upper canopy but are blocked from
receiving light from the sides by neighboring crowns), emergent (crowns completely
above main canopy), intermediate (crowns receive little light from above and none
from the side), overtopped or suppressed (one or more neighboring trees completely
overtop crowns), and seedlings
(Helms 1998).
crown fire:
Fire that burns in the crowns of trees and shrubs. Usually ignited by a surface fire.
Crown fires are common in coniferous forests and chaparral-type shrublands
(Brown and Smith 2000).
crown residual colonizer:
A plant species that establishes after a disturbance such as fire from seeds
that were present prior to the disturbance in crowned-stored cones or fruits
(Stickney 1989).
culm
The stem, especially the flowering stem of a grass
(Hickey and King 2000).
cyme:
A flat-topped or round-topped, determinate inflorescence in which the terminal flower blooms
first (Harris and Harris 2001).
cypsela:
A dry, single-seeded,
indehiscent
fruit with a
pappus,
common in the Asteraceae
(Harris and Harris 2001).
dehiscent:
Opening at maturity or when ripe to release contents, as with a fruit or anther
(Harris and Harris 2001).
density:
1) In plant ecology, density=(Total number of individuals)/(total number of quadrats)
(Grieg-Smith 1983).
Sometimes called abundance
(Mueller-Dombois and Ellenberg 1974),
a term usually not used in FEIS because of its ambiguity.
2) In range and wildlife ecology, the number of animals per unit area at a given time; stocking
(Ford-Robertson 1971).
determinant flowering:
Inflorescence in which the terminal flower blooms first, halting further elongation of the main axis
(Harris and Harris 2001).
dichogamous:
Having pistils and stamens that mature at different times to prevent self-fertilization
(Harris and Harris 2001).
dichotomous:
Branched or forked into 2 more or less equal divisions
(Harris and Harris 2001).
dioecious:
Having male and female flowers on separate plants
(Harris and Harris 2001).
diploid:
Having 2 full sets of chromosomes in each cell
(Harris and Harris 2001).
direct effects of fire:
Described in FEIS plant species summaries under Fire Effects; Immediate Fire Effect on Plant, and
Discussion and Qualification of Plant Response.
dispersion
Transport and diffusion of pollutants (Whiteman 2000).
dominance (dominant):
The extent to which a given species predominates in a community because of its size, abundance, or coverage (Lincoln and others 1998).
dough stage:
Developmental stage of plant in which seeds are nearly mature and of dough-like consistency; follows
milk stage
(National Academy of Sciences 1972).
duff:
Partially decomposed organic matter lying beneath the litter layer and above the mineral
soil. Includes the fermentation and humus layers of the forest floor (02 soil horizon)
(Brown and Smith 2000).
duff moisture code:
The moisture in the 2.8-inch (7 cm)- deep layer below the fine fuel layer,
assumed to be a layer of loosely compacted organic material. The duff moisture code
has a time lag of approximately 12 days. It is an indicator for the fire consumption of a
moderate duff layer or medium-diameter woody debris. The duff moisture code is always positive, but has
no maximum, and high values indicate drier litter and higher fire spread/danger than low values
(
U.S. Department of Agriculture, Forest Service, North Central Research Station 2007).
earlywood:
An annual ring of secondary xylem formed early in the growing season, with relatively large, thin-walled cells compared to cells formed late in the growing season
(Helms 1998).
ecotype:
A group of individuals having the same genotype resulting from the selective pressures of the local environment;
a locally adapted population; ecological race
(Ford-Robertson 1971,
Lincoln and others 1998).
elaiosome:
A seed appendage on some plants (for example, Viola, Helleborus spp.) that contains
oily substances attractive to ants; ants often aid in seed dispersal when these appendages are present
(Hickey and King 2000).
epicormic branching or sprouting:
A shoot arising spontaneously from an adventitious or dormant bud on the stem or branch
of a woody plant, often following exposure to increased light levels or fire
(Helms 1998).
epigeal:
A mode of seed germination in which the cotyledons are carried above the soil on the axis or hypocotyl
(Allaby 1992).
epiphyte:
Plant growing entirely aboveground, on the trunk or branches of woody plants
(Raunkiaer 1934).
eruption:
Departure from the home region (that is, a “bursting out”, emigration, or evasion from the home region);
arrival in the new area is called an
irruption
(Berthold, Peter; Bauer, Hans-Gunther; Westhead, Valarie. 2001).
escaped prescribed fire:
Prescribed fire
that has exceeded prescription or is expected to exceed prescription or, for some other reason,
meets criteria for conversion to wildfire. An escaped prescribed fire is considered a
wildfire
(National Wildfire Coordinating Group (NWCG) Fire Policy Committee 2010).
extreme fire behavior:
Fire behavior characteristics that ordinarily preclude methods of direct control
action. One or more of the following is usually involved: high rate of spread,
prolific crowning and/or spotting, presence of fire whirls, strong convection
column. Characteristics of such fires may change rapidly and dangerously.
Terms used to describe extreme fire behavior include "blowup", "flare-up", and
"fire storm"
(National Wildfire Coordinating Group 1996).
faciation:
A subdivision of a plant
association
that lacks some of the typically dominant species due to local differences in climate
(Lincoln and others 1998).
facilitation:
A positive effect of one plant or plant species upon another
(Callaway 1995,
Radosevich and others 1997).
Contrast with interference
and competition.
facilitation model of succession:
The improvement of site characteristics by early seral species, which allows for
later seral species to invade and grow; opposite of the
inhibition model of succession
(Connell and Slatyer 1977).
facultative wetland species:
A species that usually occurs in wetlands but is occasionally found in nonwetlands
(U.S. Department of Agriculture, Natural Resources Conservation Service 2012).
fen:
A wetland that derives most of its water from moving ground- and surface
waters that are rich in calcium and magnesium and therefore
minerotrophic;
usually less acidic than a
bog
and dominated by mosses (Bryopsida) and/or sedges (Cyperaceae) on a peat substrate
(Nevada Division of Water Planning [n.d.],
Palmer 2003).
fern ally:
A diverse group of primitive vascular plants of classes other than Filicopsida
(true ferns); includes clubmosses, spikemosses, horsetails, quillworts, wisk
ferns, adder's-tongues, moonworts, and grape-ferns
(Warner and Rubec 1997).
fire avoidant:
See fire-resistant species.
fire cycle:
Length of time for an area equal to the entire area of interest to burn; size of the
area of interest must be clearly specified
(McPherson and others 1990).
fire duration:
The length of time that combustion occurs at a given point
(McPherson and others 1990).
Fire duration relates closely to downward heating and fire effects below the fuel
surface as well as heating of tree boles above the surface.
fire exclusion:
The policy of suppressing all wildland fires in an area
(Smith 2000).
fire-free interval:
See fire-return interval.
fire frequency = fire occurrence:
Number of fires per unit time in a specified area
(McPherson and others 1990).
Ideally, the size of the area should be specified.
fire intensity:
A general term relating to the heat energy released in a fire (Keeley 2009, McPherson and others 1990).
Wherever possible, FEIS uses more specific terms to describe rate of heat release. See
fireline intensity below.
fire interval:
See fire-return interval.
fire management:
All activities related to the management of wildland fires, including fire prevention, fire suppression, and use of prescribed fire
(National Wildfire Coordinating Group (NWCG) Fire Policy Committee 2010).
fire-return interval:
Number of years between two successive fires in a designated area (that is, the
interval between two successive fires); the size of the area must be clearly specified
(McPherson and others 1990).
Usually indicates
composite fire interval, but may indicate
point fire interval.
fireline intensity:
The rate of heat release per unit time per unit length of fire front. Numerically,
the product of the heat of combustion, quantity of fuel consumed per unit area in the fire front,
and the rate of spread of a fire, expressed in kW/m
(McPherson and others 1990).
Not synonymous with fire severity,
which refers to the degree of environmental change caused by fire.
fire regime:
Describes the patterns of fire occurrence, size, and severity—and sometimes, vegetation
and fire effects as well—in a given area or ecosystem
(Agee 1994, Mutch 1992,
Johnson and Van Wagner 1985).
A fire regime is a generalization based on fire histories at individual sites. Fire regimes can often be described as cycles
because some parts of the histories usually get repeated, and the repetitions can be counted and measured. According to
Agee (1994),
"A fire regime is a generalized way of integrating various fire characteristics. The organization may be according to the characteristics of the disturbance..., dominant or potential (climax) vegetation on the site..., or fire severity, the magnitude of effects on dominant vegetation".
According to Mutch (1992),
"A natural fire regime is the total pattern of fires over time that is characteristic of a natural region or ecosystem. The classification of fire regimes includes variations in ignition, fire intensity and behavior, typical fire size, fire return intervals, and ecological effects."
According to Johnson and Van Wagner (1985),
"fire regime is a multivariate system characterized by (i) the fire history measured in fire frequency or fire return period,
(ii) fire intensity measured in kW/m, and (iii) depth of burn (duff removed) measured in kg/m, or percent".
fire-resistant species:
Species with morphological characteristics that give it a lower probability of being injured or killed by fire than a
fire sensitive
species (McPherson and others 1990). Implies that the organism does not get injured by things that would seem able
to injure it (Johnson and Van Wagner 1985). Rowe (1983)
uses a more restrictive definition of resistance - relating it only to plants with aboveground parts that survive fire.) According to
Levitt (1980), there are 2 kinds of fire resistance:
(1) Tolerance,
which describes species that mitigate dangerous, often lethal conditions. In regard to fire, tolerance
means that living cells are severely heated but survive anyway—such traits are rare.
(2) Avoidance,
which describes ways of preventing cells from heating to lethal temperatures. Most plant cells that survive fire do so through "avoidance"—because of insulating tissues, for example, or because of an insulated microenvironment. Since Rowe (1983) uses avoidance with a meaning different from this one, FEIS usually uses "resistance" to indicate both "fire tolerance" and "fire avoidance".
fire rotation interval:
The time required to burn the equivalent of a specified area
(Bond and Keeley 2005).
fire-sensitive species
A species with a "relatively high" probability of being injured or killed by fire
(McPherson and others 1990). Compare with
fire-resistant species
fire severity:
Fire severity is defined and measured in several ways. FEIS uses the term to indicate the degree of environmental change caused by fire (following
NWCG 1996, Ryan and Noste 1985).
A similar definition is: the effect of a fire on ecosystem properties, usually defined by the degree of soil heating or mortality of vegetation
(Scott and Reinhardt 2007). Other definitions of fire severity include the product of fire intensity and residence time
(McPherson and others 1990, Agee 1994, Rowe 1983)
and aboveground and belowground organic matter consumption from fire (Keeley 2009). Parsons and others
(2010)
distinguish between soil burn severity and vegetation burn severity, depending on the indicators used to determine severity.
Because “fire severity” is not used consistently in the literature, Jain and others (2004)
recommend that it be defined and the measurement method explained whenever it is used quantitatively.
fire suppression:
Any management action taken to extinguish a
wildland fire or confine its spread
(National Wildfire Coordinating Group (NWCG) Fire Policy Committee 2010).
fire tolerant:
See fire-resistant species.
fire use:
See use of wildland fire.
fitness:
A measure of the contribution of a given genotype to the subsequent generation relative to that of other genotypes
(Lincoln and others 1998).
flame length:
The length of flames in a fire front measured along the slant of the flame, from the midpoint of its base to its tip. Flame length is mathematically related to fireline intensity and tree crown scorch height
(Brown and Smith 2000).
follicle:
A dry, dehiscent
fruit consisting of a single carpel that opens along a single side, characteristic of milkweeds (Asclepiadaceae)
(Harris and Harris 2001).
foraging techniques or maneuvers:
flycatching or hawking: Flying from a perch to take aerial prey
(Airola and Barrett 1985).
gleaning: Taking stationary prey from the surface of a substrate while standing
(Airola and Barrett 1985, Pasinelli and Hegelback 1997).
hovering: Taking prey from a substrate while in flight.
lunging: Leaping from a stationary position to take moving prey
(Airola and Barrett 1985).
probing: Searching for and taking prey from within a substrate
(Castillo-Guerrero and others 2009,
Pasinelli and Hegelback 1997) such as soil, bark, or litter
(Remsen and Robinson 1990).
Remsen and Robinson (Remsen and Robinson 1990) provide a foraging classification system specific to terrestrial birds.
formation:
The broadest level in the vegetation classification hierarchy; describes stand structure (for example, closed forest, woodland, or dwarf shrub). Also see
subformation, series, and association
(Hunter and Paysen 1986):
Vegetation classification hierarchy (Hunter and Paysen 1986) |
Formation ↓ |
Subformation ↓ |
Series ↓ |
Association |
founder effect:
Where only a small fraction of the genetic variation of a parent population or species is present in the small number of founder
members of a new colony or population
frequency:
(Number of occupied quadrats)/(total number of quadrats) × 100
(Grieg-Smith 1983).
Although frequency can be used in a qualitative sense
(Ford-Robertson 1971),
FEIS does not usually use the term in this way.
fresh:
A soil moisture regime where the soil has neither a water surplus nor a water deficit in the growing season (that is, actual evapotranspiration equals potential evapotranspiration). In the Canadian forest site classification, fresh lies on a gradient between dry forest and wet forest
(Fons and Klinka 1998, Klinka and others 1984,
Ringius and Sims 1997, Rowe 1956).
fronds:
A large, divided leaf; characteristic of palms or ferns
(Harris and Harris 2001).
fuel:
Fuel is comprised of living and dead vegetation that can be ignited. It is often classified as dead or alive and as natural fuels or from logging operations). Fuel components refer to such items as downed dead woody material by various size classes, litter, duff, herbaceous vegetation, live foliage, etc.
(Brown and Smith 2000).
fuel class:
A set of fuels with similar traits. Fuels are categorized as herbaceous or woody and live or dead. Dead fuels are classed as 1-, 10-, 100-, or 1,000-hour timelag fuels, based on the time needed for fuel moisture to come into equilibrium with the environment
(
National Wildfire Coordinating Group, Incident Operations Standards Working Team 1996):
1-hour timelag fuels: Dead fuels comprised of herbaceous plants or woody plants less than about 0.25 inch (6.4 mm) in diameter and the surface layer of litter on the forest floor.
10-hour timelag fuels: Dead fuels comprised of wood from 0.25 to 1 inch (0.6-2.5 cm) in diameter and the litter from just beneath the
surface to around 0.75 inch (1.9 cm) below ground.
100-hour timelag fuels: Dead fuels comprised of wood from 1 to 3 inches (2.5-7.6 cm) in diameter and litter from around 0.75 to about 4 inches (1.9-10 cm) below ground.
1,000-hour timelag fuels: Dead fuels comprised of wood from 3 to 8 inches (7.6-20.3) in diameter and the forest floor layer >4 inches (10 cm) below ground.
fuel continuity:
A qualitative description of the distribution of fuel both horizontally and vertically. Continuous fuels readily support fire spread. The larger the fuel discontinuity, the greater the fire intensity required for fire spread
(Brown and Smith 2000).
fuel loading:
The weight per unit area of fuel, often expressed in tons/acre or tonnes/hectare. Dead woody fuel loadings are commonly described for small material in diameter classes of 0 to 1/4, 1/4 to 1, and 1 to 3 inches and for large material in one class greater than 3 inches
(Brown and Smith 2000).
fuel moisture:
Percent or fraction of oven dry weight of fuel. It is the most important fuel property controlling flammability. In living plants it is fluctuations vary considerably by species but are usually above 80 to 100%. As plants mature, moisture content decreases. When herbaceous plants cure, their moisture content responds as dead fuel moisture content, which fluctuates according to changes in temperature, humidity, and precipitation
(Brown and Smith 2000).
full-tree harvesting:
Cutting and removing an entire upper portion of a tree consisting of trunk, branches, and leaves or needles
(Ontario Ministry of Natural Resources 2003).
gametophyte:
The sexual stage in the life cycle vascular plants, when the chromosomes in each cell are reduced to half the usual number, typically diploid reduced to haploid. Gametophyte plants are small and inconspicuous (compare
sporophyte)
(Harris and Harris 2001, Hickey and King 2000).
geitonogamy:
Pollination between flowers on the same plant
(Harris and Harris 2001).
gemma:
A cell or cluster of often bud-like cells, borne on the
gametophyte,
that can reproduce the plant vegetatively.
Plural: gemmae
(Conard, Henry S. 1956).
genet:
A unit or group derived by asexual regeneration from a single original zygote; a clone
(Lincoln and others 1998).
genotype:
The hereditary or genetic constitution of an individual; all the genetic material of a cell (usually only nuclear material); all the individuals sharing the same genetic constitution
(Lincoln and others 1998).
geophyte:
Plant with perennating tissue below the soil surface; may possesses tuberous underground stems filled with stored food (for example,
bulb,
corm,
rhizome, stem tuber)
or sprout from root tissue
(Raunkiaer 1934).
geotrophism:
The response of plants in either growth or position to the pull of gravity. Geotrophic response is positive when the
response is towards the earth's center of gravity (for example, early root growth) and negative when away from it
(for example, early stem growth)
(Helms 1998).
graminoid:
A grass or grasslike monocot; includes the sedge (Cyperaceae), rush (Juncaceae), arrowgrass (Juncaginaceae), grass (Poaceae), and cattail (Typhaceae) families.
(Hickey and King 2000, Kuchler 1949).
gravid:
Carrying eggs or young
(Lincoln and others 1998).
grass/fire cycle:
An altered fire regime that may result when nonnative invasive grass species dominate the herbaceous layer in a plant community. The process occurs in this way: the nonnative grass colonizes an area and provides a continuous fine fuel that is readily ignited and facilitates fire spread. Larger and possibly more severe fires then occur more frequently in the invaded area than in similar,
uninvaded communities. Following these grass-fueled fires, nonnative grasses typically recover more rapidly than native species,
further increasing the probability of fire and the possibility of greater fire size and severity and decline of native species
(adapted from
D'Antonio and Vitousek 1992; also see
Brooks and others 2004).
greenstrip:
A long, narrow band of fire-retardant vegetation that is created by seeding
(Davison and Smith 2008).
ground fire:
Fire that burns in the organic material below the litter layer, mostly by smoldering combustion. Fires in duff, peat, dry or dead moss and lichens, and/or punky wood are typically ground fires
(Brown and Smith 2000).
ground residual colonizer:
A plant species that establishes after a disturbance such as fire from soil-stored seed that was already on site prior to the disturbance (Stickney 1989).
gynodioecious:
Plant species with female and
perfect
flowers on separate plants
(Harris and Harris 2001).
gynomonoecious:
Plant species with female and
perfect
flowers on the same plant
(Harris and Harris 2001).
hammock (hummock):
1) In the southern United States, especially Florida, a tract of hardwood forest that rises above an adjacent marsh.
2) A ridge or hill of ice or an ice field
(Nevada Division of Water Planning [n.d.]).
haplotype:
The collective genotype of a number of closely linked
loci;
the constellation of alleles present at a particular region of a chromosome
(Lincoln and others 1998).
hardwood:
1) Angiosperm trees or
2) the xylem of angiosperm trees.
The wood of hardwood trees may be physically hard (high specific gravity) or soft (low specific gravity)
(Helms 1998).
headfire:
A fire spreading or set to spread with the wind
(
National Wildfire Coordinating Group, Incident Operations Standards Working Team 1996).
heath:
Species within the plant families Ericaceae, Empetraceae, and/or Diapensiaceae. A heathland is dominated by species in those families
(Bliss 1988).
helophyte:
Freshwater plant with perennating tissue in water or saturated soil beneath water
(Raunkiaer 1934).
hemicryptophyte:
Herbaceous perennial or biennial plant with perennating tissue at the soil surface
(Raunkiaer 1934).
hermaphrodite:
Having both male and female reproductive organs in the same individual
(Lincoln and others 1998). For plants, also see
perfect.
hibernaculum:
A shelter in which animal(s) hibernate or overwinter
(Averill-Murray and others 2002,Lincoln and others 1998).
hibernation:
The act or condition of passing the winter in a dormant state characterized by
a slowing of metabolic processes that is more dramatic than
torpor;
typically involving the abandonment of thermal homeostasis in mammals
(Elphick and others 2001, McFarland 2006,
Lincoln and others 1998). Compare to
aestivation.
homogamous:
Having pistils and stamens that mature at the same time
(Harris and Harris 2001).
hybrid swarm:
A group of morphologically distinctive individuals that results from the creation of hybrids between two parent species, then the backcrossing of the offspring to members of the parent species and the interbreeding among the hybrid individuals
(BioTech Resources Web Project 1999).
hydroperiod:
The frequency and duration of inundation or saturation of an ecosystem. In the context of characterizing wetlands, the term describes that length of time during the year that the substrate is either saturated or covered with water.
hydrophyte:
Freshwater plant with perennating tissue below the surface of the water; vegetative shoots are submerged and leaves are submerged or floating; only flowers rise above the water surface
(Raunkiaer 1934).
hypanthium:
A cup-shaped extension of the floral axis, usually formed from the union of the basal parts of the calyx, corolla, and stamens, commonly surrounding or enclosing the pistils.
Plural: hypanthia.
(Harris and Harris 2001).
hypocotyl:
The portion of the embryonic shoot below the
cotyledon and above the
radicle
(Allaby 1992).
hypogeal:
A mode of seed germination in which the
cotyledons
remain below ground
(Allaby 1992).
imperfect:
A flower having either pistils or stamens, but not both; unisexual
(Harris and Harris 2001).
importance value:
A measure of overall importance of a given species in a community (Lincoln and others 1998). Definitions are inconsistent. Importance value is often calculated as the sum of relative frequency, relative density, and relative dominance, where relative dominance is synonymous with relative basal area (Grieg-Smith 1983, Lincoln and others 1998) or some similar measure (Allaby 1992, Mueller-Dombois and Ellenberg 1974). When importance value is defined otherwise, FEIS should define the term as used by the author cited.
indehiscent:
Not opening at maturity
(Harris and Harris 2001).
indeterminant flowering:
Inflorescence in which the outer or lower flowers open first
(Harris and Harris 2001).
indicator value:
Product of the relative abundance and relative frequency of occurrence for a species in group samples
(Dufrene and Legendre 1997).
inhibition model of succession:
The hindrance of subsequent species colonization or suppression of growth of species already present due to establishment of earlier colonists; opposite of the
facilitation model of succession
(Connell and Slatyer 1977).
initial off-site colonizer:
A plant species that establishes in early succession from seed dispersed onto the disturbed site
(Stickney 1989).
interference:
The negative effect of one organism upon another, regardless of the presence of a limiting resource.
Competition
is one facet of interference;
allelopathy is another
(Birch 1957, Harper 1961).
Note, however, that use of this term in the ecological literature is inconsistent;
Harper (1977), Hall (1974), and
Radosevich and others (1997)
use "interference" to refer to both positive and negative interactions between organisms.
introgression:
The spread of genes of one species into the gene pool of another by hybridization and
backcrossing
(Lincoln and others 1998).
invasive species:
A species that can establish, persist, and spread in an area
(Mack and others 2000, Sakai and others 2001).
In addition, the species must cause-or have potential to cause-harm; in natural areas, "harm" usually occurs in the form of significant changes in ecosystem composition, structure, or function
(Westbrooks 1998).
Randall (1997)
states this idea pragmatically: A plant species must interfere with management goals to be considered invasive. A nonnative species is not invasive simply because it is present in a wildland ecosystem; it must also have impacts on the ecosystem that interfere
with attainment of management objectives. Fire-related impacts of nonnative invasive plants may include changes in the species composition or structure of postfire plant communities, especially when these changes occur at the expense of native species, and changes in fuel properties that alter fire behavior or fire regimes.
involucre:
A whorl of bracts below an inflorescence or cone
(Allaby 1992, Hickey and King 2000).
irruption:
An irregular, periodic migration where large parts of a population leave their home region and move into unusual areas for a season (that is a “bursting in”, immigration, or invasion into other regions). It may be triggered by high population densities, food shortages, or both. An irruption differs from true migration because it is
irregular and does not necessarily have a return movement matching the outward movement (also see
eruption)
(Berthold, Peter; Bauer, Hans-Gunther; Westhead, Valarie. 2001).
karyotype:
The appearance of the chromosomal makeup of a somatic cell in an individual or species, including the number and arrangement and size and structure of the chromosomes
(Lincoln and others 1998).
ladder fuels:
Shrubs and young trees that provide continuous fine material from the forest floor into the crowns of dominant trees
(Smith 2000).
latewood:
An annual ring of secondary xylem formed late in the growing season, with relatively smaller, thicker,
denser, and darker cells than cells formed early in the growing season
(Helms 1998).
layering:
A form of vegetative reproduction in which an intact branch develops roots as the result of contact with soil or other media
(Helms 1998).
leaf-area index:
Ratio of total leaf area (one side of leaf only) to total ground surface, a unitless measure
(Mueller-Dombois and Ellenberg 1974).
liana:
A climbing woody plant
(Kuchler 1949).
lignotuber:
A woody storage structure forming a swelling, more or less at ground level, from which dormant buds can develop
(Helms 1998).
Functionally and ecologically similar to
burls
that occur at ground level of some woody species
(James 1984).
litter:
Recently fallen plant material that is only partially decomposed and is still discernable
(Lincoln and others 1998).
locus:
The position of a given gene on a chromosome.
Plural: loci
(Lincoln and others 1998).
lodging:
A permanent disconnection of the stem from its upright position
(Allaby 1992).
long-term effects:
Effects lasting more than 10 years
(personal communication 1998 October 21 with Wendell Hann, Fire Ecologist and assistant to National Fuels Specialist,
U.S. Department of Agriculture, Forest Service).
low-severity fire:
A fire that kills or top-kills a relatively small proportion (less than 25% according to
Hann and others 2008,
less than 20% according to
Smith (2000)
of the upper layer of vegetation. Low-severity fires can open a fuel canopy or maintain an open canopy
(Hann and others 2008).
mafic:
Containing or relating to a group of dark-colored minerals, composed predominantly of the ferromagnesium rock-forming silicates, such as olivine and pyroxene (Parker 2003).
marsh:
A low-lying wetland that has shallow water; water levels that fluctuate daily, seasonally, or annually due to tides, flooding, evapotranspiration, groundwater recharge, and/or seepage losses; is vegetated with monocots; and does not accumulate appreciable peat deposits. Marshes often form a transitional zone between water and land
(Nevada Division of Water Planning [n.d.],
Warner and Rubec 1997).
mast:
1) Exceptionally high seed production
(Lincoln and others 1998).
2) Seeds of all plants used by wildlife, including seeds with fleshy exteriors (such as berries) and seeds with dry or hard exteriors (such as nuts and cones). Collectively, the fruit of masting species
(McShea and Healy 2002).
mean fire-free interval:
See mean fire interval.
mean fire interval:
Arithmetic average of all
fire intervals
determined, in years, for a designated area during a specified time period; the size of the area and the time period must be specified
(McPherson and others 1990).
mesic:
Pertaining to conditions of moderate moisture or water supply
(Smith 2000).
metapopulation:
A population structure in which individual populations exist on patches that are dynamic in space and time
(Helms 1998).
These indiviudal or subpopulations are connected by pathways of immigration and emigration, and exchange of individuals occurs between subpopulations. Emigrating individuals are able to colonize currently unoccupied patches of suitable habitat, including previously occupied patches from which the species has recently become extinct
(Lincoln and others 1998).
milk stage:
Developmental stage of plant in which seeds are well formed but soft and immature; precedes
dough stage
(National Academy of Sciences 1972).
minerotrophic:
A site with high dissolved mineral content, with the nutrients intruded from groundwater
flow in addition to precipitation. Compare with
ombotrophic
(Warner and Rubec 1997).
mire:
A bog or
fen;
also referred to as a carr
(Nevada Division of Water Planning [n.d.]).
mixed-severity fire:
Fire that either causes selective mortality in dominant vegetation, depending on different species’ susceptibility to fire, or varies
in time or space between understory and stand replacement
(Smith 2000).
Mixed-severity fires include patchy, mosaic-creating fires and other fires that are intermediate in effects
(Hann and others 2008).
mixed-severity fire regime:
Fire regime in which fires either cause selective mortality in dominant vegetation, depending on different species’ susceptibility to fire, or vary between understory and stand replacement
(Smith 2000).
Mixed-severity fires include patchy, mosaic-creating fires and other fires that are intermediate in effects
(Hann and others 2008).
mixing depth
Vertical distance between the ground and the altitude to which pollutants are mixed by turbulence
caused by convective currents or vertical shear in the horizontal wind (Whiteman 2000).
monocarpic:
Flowering and bearing fruit only once and then dying; term can apply to annuals, biennials, or perennials
(Harris and Harris 2001).
monoecious:
Male and female flowers borne on the same plant
(Harris and Harris 2001).
monoestrous:
Having one reproductive cycle or breeding period per year
(Lincoln and others 1998).
monopodial:
Having branches arise from a single main axis
(Harris and Harris 2001).
mosaic fire:
A landscape-scale mixed-severity fire that produces scattered patches of burned and unburned vegetation
(Hann and others 2008).
muskeg:
A swamp or
bog
formed by an accumulation of Sphagnum moss, leaves, and decayed matter that resembles peat. Prevalent in Alaska and Canada;
part of the North American boreal forest biome
(Nevada Division of Water Planning [n.d.]).
mutualism:
An interdependent relationship in which both organisms benefit; frequently a relationship of complete dependence
(Lincoln and others 1998).
nidicolous:
Living in a nest; also used of young animals, especially birds, that remain in
the nest for a prolonged period (Lincoln and others 1998).
nonnative species:
An introduced species evolved elsewhere that has been transported and purposefully or accidentally disseminated by humans
(for FEIS purposes, in North America)
(Li 1995).
nonrefractory:
In FEIS, seeds that germinate in the absence of fire related stimuli; seeds may germinate readily upon wetting or they may have a dormancy that is overcome by some factor unrelated to fire
(Keeley 1991).
old-growth stage:
Fourth stage of forest stand development following major disturbance, as described by
Oliver (1981).
In this stage, stems in the overstory gradually die out and stems in the understory slowly replace them. Also see
stand initiation stage,
stem exclusion stage, and
understory reinitiation stage.
oligohaline:
1) An organism that is tolerant of only a moderate range of salinities.
2) Brackish water with a salinity from 0.3 to 3.0 parts per thousand, or sea water with a salinity from 17 to 30 parts per thousand
(Lincoln and others 1998).
oligotrophic:
A lake or other body of water with extremely low dissolved mineral content, resulting in very moderate productivity
(Nevada Division of Water Planning [n.d.]).
ombotrophic:
A site with low dissolved mineral content, with the nutrients coming exclusively from precipitation. Compare with
minerotrophic
(Warner and Rubec 1997).
ontogeny:
The growth and physical development of an individual
(Lincoln and others 1998).
organic soils:
Deep layers of organic matter that develop in poorly drained areas such as bogs, swamps, and marshes
(Brown and Smith 2000).
orthotrophic:
An orientation or growth response in a straight line. Also see
phagiotrophic
(Lincoln and others 1998).
ovoviviparous:
Producing fully formed eggs that are retained and hatched inside the maternal body, with the release of live offspring
(Lincoln and others 1998).
pappus:
The modified calyx of the Asteraceae, consisting of awns, scales, or bristles at the apex of the
achene
(Harris and Harris 2001).
parturition:
The act of giving birth
(Lincoln and others 1998).
passive crown fire:
A type of crown fire in which the crowns of individual trees or small groups of trees burn, but solid flaming in the canopy cannot be maintained except for short periods. Passive crown fire encompasses a wide range of crown fire behavior, from occasional torching of isolated trees to nearly active crown fire. Passive crown fire is also called torching or candling. A fire in the crowns of the trees
in which trees or groups of trees torch, ignited by the passing front of the fire. The torching trees reinforce the spread rate, but these fires are not basically different from surface fires
(Scott and Reinhardt 2007).
peat:
Organic soil material formed by partial decomposition of plants, especially Sphagnum spp. mosses, in water
(Nevada Division of Water Planning [n.d.],
Soil Science of America. 2001.).
peatland:
An ecosystem in which organic matter is produced faster than it decomposes, resulting in an accumulation of partially decomposed vegetative matter (Nevada Division of Water Planning [n.d.]).
To distinguish between peatlands and peaty mineral soils, minimum depths of organic deposits are sometimes set at 8 to 12 inches
(20-30 cm) in the United States (Heinselman, Miron L. 1963); in Canada, the minimum depth of organic deposits required for classification as peatland is 16 inches (40 cm)
(Soil Classification Working Group. 1998).
perfect:
Flowers with both male and female reproductive organs; can also be called bisexual or
hermaphroditic
(Harris and Harris 2001).
pericarp:
The fruit wall
(Allaby 1992).
perigynium:
A scale-like bract enclosing the pistil in Carex
(Harris and Harris 2001).
phanerophyte:
Woody plant with perennating tissue more than 10 inches (25 cm) above the soil surface
(Raunkiaer 1934).
phase:
A category that provides functional or technical detail at any level
(formation, subformation, series, and association)
of the vegetation classification system hierarchy
(Hunter and Paysen 1986).
phenology:
The study of the relationship between weather and climate and the timing of periodic natural phenomena such as bud bursting and flowering of plants or migration of birds
(Lincoln and others 1998).
phenotype:
The sum total of observable structural and functional properties of an organism; the product of the interaction between the
genotype and the environment
(Ford-Robertson 1971, Lincoln and others 1998).
phenotypic plasticity:
The capacity for marked variation in the phenotype as a result of environmental influences on the genotype during development
(Lincoln and others 1998).
plagiotrophic:
An orientation or growth response at an oblique angle to the vertical. Also see
orthotrophic
(Lincoln and others 1998).
philopatric:
Exhibiting a tendency to remain in the native locality. Used of species or groups that show little capacity to spread or disperse and
of individuals that tend to remain in, or return to, their home areas or domiciles
(Lincoln and others 1998).
plagiotrophic:
An orientation or growth response at an oblique angle to the vertical. Also see
orthotrophic
(Lincoln and others 1998).
point fire interval:
A composite fire interval over a relatively small area that the author considers
to be a point (for example, 1 or 2 ha). May refer to number of years between fire
scars on a single tree. Since a fire can burn through a small area without scarring any
trees, the Point Fire Interval may underestimate fire frequency
(Patton 2007, Taylor 2000). Also see
fire interval and
composite fire interval.
pollinia:
Masses of waxy pollen grains transported as a unit in many orchids (Orchidaceae) and milkweeds (Asclepiadaceae).
Milkweed pollinia are joined by a
corpusculum
(Harris and Harris 2001).
polycarpic:
Producing flowers or spores more than once during a life cycle
(Lincoln and others 1998).
polygamodioecious:
A plant that is mostly
dioecious but with some
perfect flowers
(Harris and Harris 2001).
polygamomonoecious:
A plant that is mostly
monoecious but with some
perfect flowers
(Harris and Harris 2001).
polygamous:
A mating system in which each adult may mate with more than one member of the opposite sex
(McFarland 2006).
polygyny:
A mating system in which males mate with a large number of females and father a large number of offspring
(McFarland 2006).
polyploid:
Having 3 or more complete sets of chromosomes in each cell
(Harris and Harris 2001).
polyestrous:
Having more than one breeding period per year
(Lincoln and others 1998).
population index:
Any indicator of a the size of a population (for example, mountain bluebird nests/km²)
(Ford-Robertson 1971).
potential natural vegetation:
The vegetation that would occur on a given site if disturbance by humans was excluded. It is a reflection of the environmental setting, or the biological potential of a land area to generate a specific ecosystem within the constraints of the nonanthropogenic disturbance regime on that site
(Hann and others 2008, Kuchler 1974, Tüxen 1956 as cited by
Kuchler 1969).
prescribed burn:
See prescribed fire.
prescribed fire:
Any fire intentionally ignited by management under an approved plan to meet specific objectives. Also called
a controlled burn or prescribed burn (U.S. Fish and Wildlife Service; U.S. Department of Interior, Bureau of Land Management. 1998).
An escaped prescribed fire
is considered a wildfire
(National Wildfire Coordinating Group (NWCG) Fire Policy Committee 2010).
prescribed natural fire:
Naturally ignited wildland fire that burns under specified conditions where the fire is confined to a predetermined area and produces the fire behavior and fire characteristics required to attain planned fire treatment and resource management objectives
(National Wildfire Coordinating Group, Incident Operations Standards Working Team 1996).
This term was not in official use as of 2010. See
use of wildland fire
(National Wildfire Coordinating Group (NWCG) Fire Policy Committee 2010).
presence:
A constancy class derived from samples of indefinite area
(Ford-Robertson 1971).
FEIS usually cites the original author's definition when this term is used.
presettlement fire regime:
The time from about 1500 to the mid- to late 1800s, a period when Native American populations had already been heavily impacted by European presence and before extensive settlement by European Americans in most parts of North America, before extensive conversion of wildlands for agricultural and other purposes, and before fires were effectively suppressed in many areas
(Smith 2000).
protandrous:
Mating system by which anthers release pollen before the stigma is receptive
(Harris and Harris 2001).
protogynous:
1) Mating system by which the stigma is receptive before the release of pollen
(Harris and Harris 2001).
2) A plant with perfect flowers that assumes a functional female condition before changing to a
functional male state
(Lincoln and others 1998).
radial spines:
Cacti spines that radiate from the margins of the
areole
(Benson 1982).
radicle:
The embroynic root
(Allaby 1992).
ramet:
A member or unit of a clone, which may follow an independent existence if separated from the parent
(Lincoln and others 1998).
rangeland condition:
A rating of rangeland condition based on total percentage of native "climax" vegetation within a given habitat type. This approach
assumes that climax vegetation can be determined for the habitat type
(Dyksterhuis 1949, Dyksterhuis 1958).
| Rangeland condition class | Percent of climax vegetation |
| Excellent | 76-100 |
| Good | 50-75 |
| Fair | 26-50 |
| Poor | 1-25 |
Vegetation classification hierarchy (Hunter and Paysen 1986) |
Formation ↓ |
Subformation ↓ |
Series ↓ |
Association |
Vegetation classification hierarchy (Hunter and Paysen 1986) |
Formation ↓ |
Subformation ↓ |
Series ↓ |
Association |