DecAID Terminology and Glossary

Inventory and Vegetation Condition-Related Terms

Wood Decay Element Terms

decay - The decomposition of wood by fungi

"Elements of wood decay” (or wood decay elements) in the context of the DecAID Advisor refers specifically to physical substrates, including: decay" (or wood decay elements) in the context of the DecAID Advisor:

down wood
snags (standing, entirely dead tree)
dead parts of live trees (dead limbs, dead bole parts, dead tops, etc.)
hollow living trees (chimney trees)

"Other decay elements” include those associated with terrestrial vegetation decay processes and elements that add complexity to forest vegetation as habitats for organisms. These include the following

litter
duff

"Other wood-related elements” adding complexity to forest environments:

bark (including crevices, fissures, etc.) on the live or dead tree bole and also in piles at the base of live trees, snags, or stumps
mistletoe brooms/witches brooms
live remnant (legacy) trees
others (e.g., canopy elements)

Specific definitions of these, and related, terms follow:

down wood - boles or large tree limbs on the ground, generally > 10 cm diameter
partially dead tree - a tree with some living tissue but also with some decaying or decayed wood; includes trees with dead tops, living trees with heart rot, and hollow living trees
dead parts of live trees - dead limbs, dead bole parts, dead tops, etc.; usually does not include bark, but might include heartrot
hollow living trees (chimney trees) - living trees that become hollow through heart rot
hollow dead trees - a subset of snags; see snags
snag - standing fully dead trees; includes hollow dead trees
wood decay elements (elements of wood decay) - a DecAID Advisor-specific term; refers to physical substrates related to wood decay, including: dead wood (both standing and down, and might include freshly dead but not necessarily decayed condition); and dead and/or decayed wood in standing live trees. Other elements related to wood disease include some structures such as mistletoe brooms.
live remnant (legacy) trees - any tree left in a stand from a previous stand growth cycle, especially large, older trees
remnant (legacy) snags - any snag left in a stand from a previous stand growth cycle, especially larger diameter snags
remnant (legacy) down wood- down wood (logs) left in a stand from a previous stand growth cycle, especially large down logs in moderate to advanced decay stages

Statistical Terms

tolerance interval - the range of values that represent a specific proportion or percentage of some sample or population (such as a 30%, 50%, or 80% tolerance interval), at a given level of confidence such as 95% or 90% confidence.
tolerance level(limit) - the specific value at the edge of a tolerance interval. For example, if a 30% tolerance level of snag dbh used by wildlife species in a specific vegetation condition is, say, 40 cm, this means that 30% of all individuals of the wildlife populations used less than or equal to that size snag. An 80% tolerance level would correspond to 80% of the individuals using that corresponding size snag. A 100% tolerance level means all of the individuals would use that size snag (100% tolerance intervals correspond to the maximum observed values, such as the largest dbh snag observed to be used by a wildlife species).
confidence interval - the range of values within which the average or mean value of some additional (or future) statistical sample of a population would occur, at a given level of confidence such as 95% or 90% confidence. The DecAID Advisor uses tolerance intervals instead of confidence intervals, because management questions pertain to wanting to know what percent of a wildlife population is afforded by particular sizes or amounts of snags and down wood, not what some future mean value would be.
level of "assurance" - in DecAID, refers to low, moderate, or high tolerance intervals, that is, 30%, 50%, and 80%, respectively, of the observed proportion of the wildlife populations that were reported in the literature to use or select for specific sizes or amounts of snags or down wood.

Inventory and Vegetation Condition-Related Terms

FIA – Forest Inventory and Analysis. Vegetation inventory program where data are collected on field plots that are spaced at about 3.4-mile intervals on a hexagonal grid, spanning both publicly and privately owned forests on reserved and unreserved lands.
CCplots - The FIA inventory sample design divides plots into CCplots, short-hand for “condition class”, based on a set of attributes used to classify unique conditions within a plot. Crews in the field evaluate each plot, looking at attributes that describe forest structure, composition, and disturbance. When different attributes were found on a plot, it was divided into multiple CCplots (each CCplot occupies a certain percentage of the plot). For the database and analysis, CCplots were reviewed in the office and further classified by wildlife habitat type, S-Class, ownership, harvest status, etc. These attributes were then used to group CCplots to summarize data before analysis. Only those conditions (CCplots) occupying at least 25% of the total plot area were used in the analysis.
unharvested CCplots - forest inventory plots on which no disturbance related to tree harvesting (e.g., clearcut, partial, firewood cutting and other incidental removals), other tree removal (e.g., precommercial thinning, commercial thinning, herbicide spraying) or road presence was recorded by the field crews
all CCplots - all forest inventory plots, regardless of their history of disturbance
reference condition - the current variability in dead wood populations in forests that have never been harvested, based on a summary of ‘unharvested’ inventory plots. The inventory summaries for reference conditions in DecAID describe variability across space at a single point in time (early 21st century). This is distinct from ‘historic variability’ concepts, which typically refer to variation over very long time periods (see Landres et al. 1999). See ‘caveats’ for more information on the disturbance history of the inventory plots and how it relates to historic conditions. [Landres et al. 1999., Weins et al. 2012]
current condition - the actual, current forest condition given all historic and modern human disturbances (including harvests, fire management, etc.); compare with reference condition
DecAID Successional Structure Class(S-Class) - a DecAID Advisor-specific term; refers to structural condition categories that, in general, follow the typical successional pathway for forests in the region. S-classes) are based primarily on the size of trees that dominate the structure of the stand. The S-classes correspond to the classification scheme from Haugo et al. (2015). Only 3 classes were used to create data pools to best reflect wildlife use based on available data; these 3 classes are open Early, Mid, and Late
SHP Structural Condition Categories - 26 classes of structural and successional stages of development of SHP wildlife habitat types
DecAID Vegetation Condition - a DecAID-specific term referring to the specific combinations of DecAID wildlife habitat type, DecAID forest inventory subregion where applicable, and DecAID successional structure class; an example of a DecAID vegetation condition is “Westside Lowlands Conifer/Hardwood Forest DecAID wildlife habitat type, Washington Coast DecAID forest inventory subregion, Early DecAID S-class.”
DecAID Vegetation Condition Code - a DecAID-specific abbreviation for the vegetation conditions used in the DecAID Advisor
DecAID Wildlife Habitat Type - combinations of habitat type from the Species Habitat Project (Johnson and O’Neil 2001) and DecAID alliance groups
DecAID Grouping of TNC Alliances - alliances as defined by the National Vegetation Classification System (Grossman et al. 1998), as grouped for the DecAID Advisor
DecAID Forest Inventory Subregion - a DecAID-specific term; a geographic area within Oregon and Washington based on physiographic province delineations and defined based on location information and the Wildlife Habitat Type.
Species Habitat Project (SHP) Wildlife-Habitat Type (Johnson and O'Neil 2001) - 32 wildlife habitats identified in Washington and Oregon, 10 of which are the forest and woodland types considered in DecAID. (The SHP Wildlife-Habitat Types were derived from clustering a set of vegetation conditions based on wildlife species occurrence. Thus, the term 'habitat' is correctly used in this regard, where habitat refers specifically to use by species or organisms.)
decay stage - for snags, a 5-class scheme of hard, moderate, and soft; for down wood, a 5-class scheme ranging from hard to decayed
down wood diameter - depending on data available and literature source, refers to diameter of down wood at the large end, small end, midpoint, or point of intersection with a transect line; for future use in DecAID, this should refer to large end diameter
dbh - Diameter at breast height. Tree diameter measured at 4.5 ft from the ground.
snag dbh - refers to diameter at breast height measured around whatever wood is present and over bark if present
top condition - refers to whether a snag has an intact top or broken top

Wildlife-Related Terms

key ecological function - the major ecological roles of organisms (viz., wildlife species)
key environmental correlate - the major features of habitats, substrates, and environmental conditions to which the presence or abundance of organisms (viz. wildlife populations) significantly correlate
ecosystem processes - biophysical process related to nutrient cycling, organic matter decomposition, and energy flow, related to wood decadence in forests

Insect and Disease-Related Terms

abdomen - Posterior or hindmost portion of an insect's three main body divisions.
abiotic - Nonliving factors such as temperature, moisture, and wind.
adult - Full-grown, sexually mature insect; usually has wings, in contrast to larvae, which lack wings.
aecia - Plural form of aecium. One of the many types of fruiting bodies formed during the life cycle of rust fungi; a cup-like structure producing aeciospores. anamorph - Imperfect state of a fungus; produces asexual spores.
annual - An event that occurs once a year, or something that lasts one year or season; also, completing the life cycle in one year.
Ascomycete - A class of fungi that produces spores in a sac-like structure called an ascus.
arthropod - An invertebrate creature characterized by an exoskeleton, segmented body, and paired, jointed limbs; includes insects, arachnids, and crustaceans.
Basidiomycete - A class of fungi that produces spores in or on the outside of a structure called a basidium.
blight - A disease or injury that results in rapid discoloration, withering, cessation of growth, and death of parts without rotting.
boring dust - Tiny particles of bark or wood produced by insects as they tunnel in woody plant structures.
brood - All of the bark beetle offspring produced by a single set of parents that hatch and mature at about the same time.
broom - An abnormal proliferation of branches or twigs on a single branch.
brown rot - A light to dark brown decay of wood that is friable and rectangularly checked in the advanced stage; caused by fungi that attack mainly the cellulose and associated carbohydrates. Residue left is predominantly lignin.
buff - Off-white, cream, to yellow-tan color.
cambium - Layer of actively dividing cells between the xylem (sapwood) and the phloem (inner bark)of trees, which forms additional conducting tissue, therefore increasing the girth of a stem, branch, or trunk.
canker - An oval or circular killed area on a stem or branch; usually with a shrunken surface.
chlorotic/chlorosis - Yellow appearance of normally green foliage caused by loss or lack of chlorophyll.
cocoon - A covering spun or constructed by a larva as a protection to the pupa.
cohort - A group of individuals having a common statistical factor such as age, e.g. all of the foliage produced during the same year.
conk - The large, often bracket-like fruiting bodies of wood-consuming fungi (Basidiomycetes).
context - The interior or body portion of a conk or a mushroom. The context supports the reproductive structures.
cryptic - Hidden or concealed; not readily apparent.
cubical decay - Decayed wood breaking up into distinct cubes.
decline - Gradual reduction in health and vigor as a tree is in the process of dying slowly.
defoliation - Premature removal of foliage.
defoliator - An insect or pathogen that feeds on the living tissues or plant sap in foliage; physically removes needles or portions of needles, or causes tissue necrosis and premature needle drop.
delaminating decay (laminate decay) - Selective, more extensive decay in the spring wood than the summer wood causing the wood to separate into sheets or laminae along annual rings.
dessication - Rapid drying of plant parts.
dieback - Dead apical parts, usually twigs or limbs; also the process of dying from the outside in.
disease - A prolonged disturbance of the normal form or function of a tree or its parts.
distal - Near or toward the free end of an appendage; far from the point of attachment or origin.
distress cones (stress cones) - A cone crop produced as the result of tree stress; often associated with root diseases. Cones may be produced relatively early in the tree's life and are often very numerous and small in size with high percentages of nonviable seeds.
ectotrophic mycelia - Fungal growth on the outside of a root or within the fissures of root bark.
egg gallery - Tunnel constructed under the bark of host trees by adult beetles for the purpose of laying eggs. Egg galleries maintain a fairly constant width with increasing length, but are sometimes associated with wider constructions, such as entrance points and nuptial chambers.
egg niche - A small recess constructed in woody plant tissue by a female insect for the purpose of egg deposition.
elytra - Leathery front wings of beetles which cover the membranous hind wings when the insect is not in flight; not used for flying.
elytral declivity - The posterior, down-sloping portion of the elytra.
entrance court - The point of invasion of a disease organism into its host.
ephemeral - Lasting a very short time.
epicormic - Branches of foliage arising abnormally along a trunk as the result of release of dormant buds or the differentiation of buds from callus.
exotic - An introduced, or non-native, insect or pathogen.
exuva (pl. exuvae) - A hollow, cast-off pupal “skin” that remains following adult insect emergence from the pupal stage.
fascicle - An individual needle bundle or cluster on coniferous species.
flagging - Conspicuous recently dead or dying shoots or branches on a live tree that have discolored foliage still attached.
forewings - The first pair of wings from the head.
frass - Solid insect excrement, particularly of larvae; particles are usually rounded pellets.
free feeder - Refers to the feeding habit of the immature stages of many defoliating insects; free-feeding larvae live in the open upon foliage surfaces without constructed webbed shelters and do not reside in the interior of needles, buds, or expanding shoots.
fruiting body - Any of a number of kinds of reproductive structures that produce spores.
fungus (pl. fungi) - A member of the group of saprophytic and parasitic organisms that lack chlorophyll, have cell walls made of chitin, and reproduce by spores; includes molds, rusts, mildews, smuts, mushrooms. Fungi absorb nutrients from the organic matter in which they live. Not classified as plants; instead fungi are placed in the Kingdom: Fungi.
gall - Abnormal proliferation of plant tissue, stimulated by insects, pathogens, or abiotic influences.
gallery - A tunnel constructed by an insect in which it lives, feeds, or deposits eggs.
gelatinous - Resembling gelatin or jelly.
gouting - Abnormally thickened or swollen branch tips or branches, caused by insects, pathogens, or abiotic influences.
gregarious - Living or feeding in groups.
grub - Thick-bodied, usually sluggish, larva.
hard pines - Pines having 2 or 3 needles per fascicle (rarely 5 to 8); needle cross-section shows 2 fibrovascular bundles; wood is hard, with an abrupt transition from spring wood to summer wood; cone scales are usually thick at the apex and have a short spine; species native to Oregon and Washington include ponderosa pine Jeffrey pine, knobcone pine (OR) and lodgepole pine.
heartrot - A decay restricted to the heartwood.
heartwood - Central mass of tissue in tree trunks; contains no living cells but functions as mechanical support.
hindwings - The second pair of wings from the head.
honeydew - Sugary liquid excretion of aphids or scales.
hyphae - Microscopic filaments of fungal cells.
hysterothecia - Elongated fungal fruiting bodies that open with a slit, found in Ascomycete fungi. Common to many needle cast fungi.
incipient decay - The earliest stages of wood decay in which the wood may show discoloration but is otherwise not visibly altered.
infection - The act of a pathogen establishing itself on or within a host.
larva (plural larvae) - An immature form of an insect that undergoes complete metamorphosis, such as a caterpillar, grub, or maggot.
larval gallery - Tunnel constructed by developing beetle larvae as they feed under the bark. Larval galleries tend to grow wider with length.
lateral - A branch that arises from a whorl along the vertical axis of the conifer tree bole and extends outward to form an angle that typically ranges between 45 and 225 degrees.
lesion - A localized zone of dead or dying tissue.
longitudinal - Placed or running lengthwise with the axis of the tree bole or limb.
maggots - Small, headless, legless, white to creamy larvae belonging to the order Diptera (flies).
molt - A process of shedding the outer layer; when molting, insects shed their exoskeleton (sometimes improperly called “skin”).
mushroom - A fleshy fruiting body of a fungus, often with a gilled pore surface.
mycelium - The collective mass of vegetative elements or hyphae, of a fungus.
mycelial fan - Dense mass of mycelium which takes the form of a thick mat that is fan-shaped.
mycelial felt - Dense mass of mycelium which takes the form of a thick mat.
necrotic - Dead; usually refers to cells or tissue killed by injury or disease.
necrosis - Localized death of living tissue, usually resulting in darkening of the tissue.
needle sheath - The thin, somewhat papery, tubular covering that surrounds the base of a pine needle fascicle.
nuptial chamber - An open, cave-like area constructed in the inner bark beneath the entrance hole by the male of some bark beetle species where mating takes place and from which the egg galleries originate. When viewed with the bark removed, nuptial chambers appear as enlarged areas at junctions or at the ends of egg galleries.
nymph - An immature form of an insect that undergoes incomplete metamorphosis; nymphs resemble the adults except for size and wing development.
Oomycete - A class of microscopic soil and water fungi that have a mobile, swimming spore stage called a zoospore and a thick-walled sexual spore called an oospore.
overwinter - To survive through winter; term commonly used when describing the life stage in which an insect passes the winter months, e.g., second instar western spruce budworm larvae overwinter.
ovipositor - A tubular or valved structure used by an insect to lay eggs, usually concealed, but sometimes extended far beyond the end of the body.
parasite - An organism living on or in and nourished by another living organism.
pathogen - An organism that causes a disease.
pathogenic - Being capable of causing disease.
patch attack - An attack by bark beetles that does not completely girdle the tree but is concentrated along one side or within a relatively confined area on the bole, resulting in death of only a portion of the bole; also called a strip attack.
perennial - An organism that lives from year-to year; persisting for several years.
pitch - A resinous exudate of various conifers.
pitch nodule - A small lump of pitch attached to a conifer branch or bole.
pitch tube - A globular mass of resin, boring dust, and frass that forms on the bark of pine trees at bark beetle entrance holes.
pitch streamers - Long, thin flows of pitch on the tree bole.
pith - The soft, spongelike center of stems and branches of woody plants.
phloem - Conductive tissue found between the sapwood and outer bark of trees or other woody plants.
phytophagous - "Plant-eating."
pocket rot - A characteristic pattern of rot that occurs in distinct, scattered pockets rather than in columns.
pore - The open end of a tube in which certain spores of higher fungi are produced.
pore layer (pore surface) - The surface of a fruiting body on which the pores are found.
posterior - The hind or rear part of the body.
primary - Organisms which are capable of invading apparently healthy hosts and causing mortality.
proleg - The fleshy, unjointed appendages found on the abdomens of caterpillars and some sawfly larvae; also called “false legs.”
pseudothecia - Tiny, round to flask-shaped fruiting bodies containing asci and ascospores and produced by certain Ascomycetes.
punk knot - Soft, decayed branch stubs that usually indicate the presence of decay in a tree.
pupa (pl. pupae) - The inactive transitional stage between the larval and adult portions of the life cycle that occurs in insects with complete metamorphosis. Characterized by a covering formed by the larva as it changes into a pupa.
pupal cell - Cavity at the end of the larval gallery in which pupation occurs.
pupate - To change from a larva into a pupa; to pass through the pupal stage.
pustule - Blisters of an infecting fungus which mature into fruiting structures.
resinosis - Reaction of a tree to invasion by pathogens, insects, or abiotic injury which results in flow of resin on the outer bark or accumulation of resin within or under bark.
rhizomorph - A specialized thread or cord-like structure made up of parallel hyphae with a protective covering.
saprot - Decay of the sapwood.
sapwood - The outer conducting layers of wood, which contain living cells and reserve material.
secondary - Organisms that are limited to invading hosts predisposed by stress or attack by some other more aggressive organism.
setal hyphae - Hyphae with hair or tooth-like protrusions that may be visible with the naked eye or under low magnification.
slash - Woody debris such as logs, bark, and branches left after logging activities.
soft pines - Pines having usually 5 (sometimes 1-4) needles per fascicle; needle cross-section with one fibrovascular bundle; cone scales usually thin at the apex and without a spine; soft wood having a gradual transition from spring wood to summer wood; species native to Oregon and Washington include western white pine, sugar pine, limber pine (OR) and whitebark pine.
solitary - Living or feeding alone.
spore - A microscopic reproductive cell or cells.
sporulate - To release spores.
springwood - Also known as “early wood”. The less-dense, larger-celled portion of an annual growth ring formed by a tree during the early part of the growing season. Springwood is usually lighter in color than summerwood.
stippling - The minutely spotted, speckled chlorosis of green foliage caused by the feeding of sucking insects.
stringy rot - Decay that results in the heartwood being reduced to fibrous material.
strip attack - An attack by bark beetles which does not completely girdle the tree, but is concentrated along one side or within a relatively confined area on the bole; results in death of only a portion of the bole; also called a patch attack.
stunted - Checked growth, dwarfed, abnormally shortened leaders and needles.
successful bark beetle attack - Bark beetle attacks, occurring on an individual tree during a single growing season, that result in tree mortality. For the purposes of coding during forest vegetation surveys, a successful attack occurs when bark beetle attacks on a tree bole are judged to be of sufficient density to cause death within one year as a direct result of those attacks. Successfully attacked trees often display one or more of the following attributes: copious amounts of orange-red boring dust on the bole, large numbers of pitch tubes, or fading, chlorotic, or red foliage.
summerwood - Also known as “late wood”. The dense, smaller celled portion of an annual growth ring formed by a tree during the latter part of the growing season. Summerwoood is usually darker in color than latewood.
suppressed - Trees with crowns overtopped by larger trees and that receive no direct sunlight from above or from the sides.
telia - Plural form of telium. One of the many types of fruiting bodies formed during the life cycle of rust fungi; produce teliospores.
terminal - The main, or primary growing tip of a conifer.
topkill - Death of the upper crown of a tree; usually caused by insects, pathogens, or weather events.
transverse - Lying or running at right angles to the axis of the tree bole or limb.
tubercle - A small rounded prominence.
unsuccessful bark beetle attack - Bark beetle attacks, occurring on an individual tree during a single growing season, that do not result in tree mortality. For the purposes of coding during forest vegetation surveys, an unsuccessful attack occurs when bark beetle attacks are judged to be of insufficient density to cause tree death within one year as a direct result of those attacks.
uredia - Plural form of uredium. One of the many types of fruiting bodies formed during the life cycle of rust fungi; produce urediospores.
vascular tissue - Plant tissue that conducts sap.
wetwood - A discolored, watersoaked condition of the heartwood of some conifers presumably caused by bacterial fermentation.
white rot - Decay caused by fungi that attack all chief constituents of wood and leave a whitish or light colored residue.
wingspan - Width of wings when extended as if for flight.
witches' broom - An abnormal proliferation of branches or twigs on a single branch.
xylem - The woody tissue of the stem, branches, and roots that transports water and nutrients.
zone line - Black or brown lines of fungal hyphae in decayed wood that resist the advance of other fungi.