Upgrade to remove ads
ISA Arborist Certification Glossary
Terms in this set (790)
pertaining to the nonliving parts of an ecosystem, such as soil particles, bedrock, air, water.
abscisic acid (ABA):
a plant hormone that stimulates stomatal closure and promotes seed and bud dormancy.
a wall of cells at the base of a petiole, that allows the leaf to separate from the stem.
the amount of risk that an owner is willing to accept before tree failure.
the establishment of a location used to enter a site.
having a pH les than 7.0, in contrast with alkaline which has a pH that is higher than 7.0.
microorganisms that have some characteristics of fungi and bacteria. Soil actinomycetes are very tolerant of water stress and contribute through their actions to that "good earth" aroma after a rain.
the number of distinct motions for the carabineers and snaps gate to be opened.
the point at which a pest requires the implementation of a management tactic or control.
stronger and wider than a co-dominant crotch, they are not likely to be a branch that will fail in high winds and are considered desirable.
an increase in wood production in localized areas on a tree, in response to a decrease in wood strength or external loading to maintain an even distribution of forces across the structure.
a boundary on the ground delineated by the branch spread of a single tree or group of trees.
adhesion on contact of molecules to the surface of solids or liquids with which they are in contact.
an assessment performed to provide detailed information about specific tree parts, defects or site conditions.
new growth arising directly from dormant or new buds on main branches, stems, or trunks often in response to moisture and light that has no connection to apical meristems.
a root arising from parts of the root or the stem, often in response to moisture and darkness that has no connection to apical meristems.
the provision of air to the soil to alleviate soil compaction.
aerial lift device:
a truck with booms and a bucket, for elevating a worker to a tree's crown; may also be mounted on a self-propelled machine known as a mini-lift.
a method of bringing an injured worker down from a tree.
roots that grow from stems toward the soil with the capacity to become prop roots when they anchor in the soil.
these microbes require free, gaseous oxygen for growth.
soil such as sand, silt, or clay, a cluster of soil particles and organic matter, bonded together by exudates from microorganisms. It is often used under paved surfaces, as backfill.
agroforestry or agro-sylviculture:
is a land use management system in which trees or shrubs are grown around or among crops or pastureland.
the commonly used trade name for an air tool.
the uppermost point of a lightning protection system in a tree. It is usually made of copper.
also called air excavation device, a device that uses a jet of compressed air to excavate soil within the root zone of trees and minimize damage to tree roots.
having a pH greater than 7.0, in contrast with acidic soil which has a pH lower than 7.0.
substances that are produced by trees and contain nitrogen and are used by humans for medicines.
two parallel rows of trees, usually of the same species, form, and age, often having canopies that have grown together.
the production of substances by one tree that adversely affect other trees nearby. Root exudates from some trees can kill or stall growth of many soil organisms.
occur when there is one bud or leaf at a node.
an enzyme that can change the starch chains back to glucose molecules.
these microbes live in the absence of free oxygen.
drop-forged eye nut is used to fasten through-hardware anchor(s), used when cabling trees.
the hardware installed to affix and/or terminate a cable or guy to the tree, ground, or other device.
a tree used to provide supplemental support in a guying installation.
hardwood trees that have covered seeds such as oaks and maples. The seed is born within an ovary.
negatively charged atoms or molecules in fertilizer that become available to the plant in water.
the American National Standards Institute.
the performance parameters established by industry consensus as a rule for the measure of extent, quality, quantity, value, or weight used to write specifications.
the American Standard for Nursery Stock, 2014 edition.
the Safety Standard that provides the most current criteria in the United States for arborists and other workers engaged in arboricultural operations.
the pollen producing part of a flower.
a chemical that gives the red pigments to leaves and other plant organs.
a substance applied to the foliage of plants to reduce water loss.
anvil-type pruning tool:
a pruning tool that has a sharp straight blade that cuts against a flat non-cutting surface.
the inhibition of growth of lateral buds by the terminal or apical bud.
meristems increase the length of stems and roots, and produce flowers.
the framework of non-living cells and cell walls in wood and bark. The apoplast stores bound water, which does not flow.
placing a monetary value on a tree.
the minimum distances between energized conductors and personnel.
the art, science, technology, and business of commercial, public, and utility tree care. Arboriculture focus is on the tree while the focus of forestry is on all trees.
an individual engaged in the profession of arboriculture who, through experience, education, and training, possesses the competence to perform the management of trees and other woody plants.
an individual undergoing on-the-job training to obtain the experience required to manage trees and woody plants. Such trainees shall be under the supervision of an arborist.
commonly called endomycorrhizae infects the internal tree root cells and are most common in deciduous forests.
armillaria root disease:
cause death to trees under all types of stress by reducing absorption and translocation of water and minerals from the soil to the tree.
microscopic insects and mites that are vital in processing soil organic matter and mineralizing detritus.
attached to the rope, this piece of equipment will grip in one direction (down) and slide in the other (up) allowing the climber to ascend up the rope in contrast with descender.
a tool that bores holes in wood.
a tree growth regulator that controls cell elongation.
cells that run in a vertical direction on the trunk.
the point of attachment of a leaf petiole to a stem.
a cut made on a tree trunk or branch, opposite from the notch, face cut, or undercut.
back flow preventer:
a device required by law to prevent water and chemical back flow by means of an air gap or one-way valve.
organisms that break down organic and inorganic materials such as fungi, insects, and animals in the soil. They also detoxify harmful substances and adjust the soil pH. Many also convert nitrogen in the air to a usable form for tree growth. Bacteria can be found everywhere that life can be supported.
Balled and Burlapped trees, also called Balled in Burlap, have been dug so the soil around the roots remains undisturbed.
Balled and Potted trees with a ball of earth and placed in a container.
a rigging sling(s), usually with at least one spliced eye and a Prusik to position the load line.
a protective covering on the outside of a tree trunk and made of an outer periderm and an inner phloem. It keeps moisture and gases in the tree and resists attack by insects and microorganisms.
overgrown knots, mechanical wounds, holes of all types, ingrown bark, and other defects which can be seen on the bark appearance.
form on trees whose bark plates only divide in one direction such as oaks. Some trees, such as beech, do not form fissures because the bark plates divide in two directions as the tree grows in girth.
chemical boundary within wood that is present at the time of wounding and resists the spread of pathogens.
decay of the lower trunk, flare, or buttress roots, also called butt rot.
a detailed visual inspection of a tree and the surrounding site.
insects and other organisms that promote plant health or assist in the control of pest populations.
soil added in a linear form above grade for a specified purpose, such as controlling the flow of water.
a simple fleshy fruit.
the natural division of a branch or stem into two or more stems.
the connector on a lightning protection system consisting of two or more types of metals intended to reduce the likelihood of forming an electrolytic couple.
capable of being broken down by natural, organic processes and reabsorbed into the environment.
biological diversity in an environment as indicated by a number of different species of plants and animals.
biological control management:
the management of pests using organisms that focus on control of plant competition, allelopathy, animals, insects, or pathogens.
a mass that contains some form of living cells.
a pesticide formulated from naturally occurring plant extracts, microbes, or microbial byproducts.
any substance or microorganism applied to plants with the aim to enhance nutrition efficiency, abiotic stress tolerance and/or crop quality traits, regardless of its nutrients content.
pertaining to living organisms and their ecological and physiological relations.
the flow of sap from plant wounds.
any disease that kills young plant tissues.
block and tackle:
a system of two or more pulleys and rope used to lift or pull heavy loads.
Best Management Practices are the best industry standards based on scientific research and current knowledge.
the main trunk of a tree below the branches.
an electrical connection between an electrically conductive object and a component of a lightning protection system that is intended to significantly reduce potential differences created by lightning currents.
the art of managing tree growth through root pruning to maintain a miniature size.
the long, movable arm of an aerial device or crane.
using the tip of a chain saw to cut into or through the middle of a piece of wood.
compounds and pesticides made from plants.
large branches on a tree coming directly from the trunk.
Bare-Root trees that are harvested and removed from all soil or growing medium.
the installation of screws, cables, threaded-steel rods in branches, leaders, or trunks to provide supplemental support and to reduce the probability of failure of one or more parts of the tree.
a modified leaf that compliments the flower.
an outward growing shoot, stem or twig that grows from the main stem or trunk of a tree.
the swollen area of bark at the underside of a branch.
branch bark ridge:
the raised area of bark at the top of the branch union that marks where the smaller branch and parent branch meet.
branch bark ridge and branch collar:
the natural features of a fork or union that consist of raised bark but may or may not be obvious. Neither the branch bark ridge nor collar should be cut when pruning the tree.
usually occurs when high winds bend the branch upwards and fracture the wood, causing the splinters to point upwards. When the branch fails and there is no wind, the splinters will point downwards.
the point where a branch originates from the trunk or another branch.
the method to used to repair a girdled trunk in which scion wood is grafted above and below the injury to reconnect the trunk vascular cambium.
the application of fertilizer over the soil surface.
the process of cutting a felled and de-limbed tree into logs.
organs that contain preformed parts of leaves or needles, flowers, or both. Buds are structures that are made up of embryonic shoots.
a scar left on a twig when the bud or bud scales fall away.
the ability of a soil to maintain its pH.
that portion of a lot wherein a building may be located, not the portion of a lot which is located within any minimum required front, rear, or side yards, landscape areas, or buffer zones.
a general enlargement of a section of a log.
the mass of soil per unit volume used as a measure of compaction.
a large diameter rope used in rigging.
a sound, hard woody protuberance on a log with no protruding branches, twigs, or stumps.
a strong, coarsely woven cloth made from fibers of jute, flax, or hemp.
the lateral surface roots that aid in stabilizing a tree.
a pruner that pushes a sharpened blade through a small-diameter stem, past an unsharpened hooked or curved blade. Also called secateurs.
1) Zinc coated wire strands per ASTM A-475 for dead-end grip applications or 2) Wire rope or strand for cabling applications or 3) Synthetic-fiber rope or webbing for general applications of tree work.
a tool used mainly to tighten lag hooks and eye-bolts into a tree.
should be used to attach small diameter cable to anchor hardware. There should be at least 3 clamps per anchor and the "U" of the clamp goes on the short end of the cable.
the hardware designed to anchor cables installed through a branch or stem.
a mechanical device that temporarily grasps and holds wire rope or strand cable during installation.
the installation of a steel wire rope or synthetic-fiber rope within a tree to provide supplemental sup-port to branches with weak unions, heavy branches, and weak wooded species that may pose a threat of failure.
consists of eye bolts, threaded rods, and amon-eyes.
tree trunk diameter measured 6 in. (15 cm) above the flare; if the caliper is greater than 4 in. (10 cm), the measurement is taken at 12 in. (30 cm) above the flare.
an instrument used to measure the diameter of the trunk of a tree.
undifferentiated cambium tissue that forms around the edge of a wound.
cambium or cambial zone:
a layer of trunk cells that produce xylem on the inner side and phloem or inner bark on the outer side.
a definite, relatively localized lesion, primarily of bark and wood.
the collective branches and foliage of a tree that make up the tree's crown.
the area of land surface that is covered by tree canopy as seen from above.
the water held in the capillary pores of soil.
a simple, dry, fruit.
a colorless gas, soluble in water, used by green plants to make carbohydrates during photosynthesis.
the capturing and long-term storage of carbon.
the yellow, orange, or red pigment responsible for those colors in parts of a tree.
the simple protecting leaf wrapped over a small bud structure.
cation exchange capacity:
the ability of soil to hold onto nutrients.
positively charged atoms or molecules in fertilizer that become plant available in water.
the long droopy flowers produced at the ends of branchlets that eventually fall from the tree.
a void within the solid structure of the tree, normally associated with decay or deterioration of the woody tissues.
the basic structural and functional unit of living organisms.
a complex carbohydrate made up of long, twisting chains of glucose or sugar molecules.
referred to as the leader or dominant leader. It is a continuation of the main trunk, beginning at the lowest main scaffold branch and extending to the top of the tree.
an arborist who has passed an independent exam administered by the ISA.
CEU or continuing education unit:
a measure and confirmation of continuing education courses.
chain of custody:
evidential documentation of the handling, transportation, processing, and ownership of a tree throughout the chronological history of its entire production.
a portable power saw with teeth linked in a loop of chain.
the largest tree by age or size when compared to all other known trees of the same species.
leg protection to be worn when operating a chain saw.
chemical compounds that keep plant nutrients soluble and available for tree absorption.
chemical management methods:
the management of pests and vegetation through the use of pesticides, herbicides, and growth regulators, to make conditions more favorable for tree growth.
equipment used to reduce tree debris into wood chips.
a hard substance forming the outer coat of insects and the cell walls of some fungi.
the green substance that can trap the energy of the sun in a process called photosynthesis.
specialized cells that contain chlorophyll and promote making starch or sugar.
the partial failure to develop chlorophyll, caused by a nutrient deficiency or the activities of apathogen.
consist of genes and are responsible for the activity of a cell and undergo division into newly formed parts of the tree.
one or more roots whose diameter is greater than 10% of the trunk caliper circling more than one-third of the trunk. Circling roots are unacceptable for proper tree root growth.
a process in which trees shed their branches as part of their normal physiology once a year, typically on cedars.
the selective pruning to remove one or more of dead, diseased, or broken branches.
the portion of the trunk below the main crown which may include shortened temporary branches.
pruning to meet clearance standards over streets and sidewalks where branches are interfering with the movement of vehicles and pedestrians, or they obstruct signs and traffic lights.
the property owner or manager who is responsible for contracting arboricultural services. Clients may be owners of property and governmental clients that are stewards for private and public lands.
the hitch used to secure a tree climber to the climbing line.
sharp, pointed devices attached to a tree climber's boot and are used to assist with climbing trees. They are also called gaffs, hooks, spurs, and spikes, and are not recommended for pruning operations, except during tree removal.
a named tree from which identical trees are produced by vegetative propagation. Cloned trees are growing on their own roots instead of being grafted to roots.
the closing of a wound to the stem or root of the tree. Closure is not CODIT.
Compartmentalization Of Decay In Trees. see "compartmentalization"
two or more, generally upright, branches or stems of roughly equal diameter and competing with each other for dominance. They originate from a common point, usually where a leader was lost. When they grow from a common union the structural integrity of that union should be assessed and one stem removed or reduced.
a tree that has been taken from the wild or landscape planting and then grown in a nursery.
a portable winching device, using cable or rope to draw two objects closer together.
a system of vocal communication in tree care operations used to convey critical information between a worker aloft and a ground worker.
weights on the soil surface that destroy the micro cavities and the many mycorrhizae that grow in the soil. The compaction of the soil reduces the oxygen content which is needed in the soil for root respiration.
the physiological process that creates the chemical and physical boundaries that act to resist the spread of disease and decay organisms.
a fertilizer containing the three primary elements: nitrogen (N), phosphorus (P), and potassium (K).
organic matter that has been subjected to decay processes and is decomposed.
a leaf whose blade is divided into several distinct leaflets.
this wood forms on the lower side of the lean in conifers, as evidenced by closely spaced rings.
the general condition of a tree rated during the inventory and according to the ISA rating system: Excellent - 100%, Very Good - 90%, Good - 80%, Fair - 60%, Poor - 40%, Critical - 20%, Dead - 0%.
the copper cable or wire used in a lightning protection system intended to carry the lightning current to ground.
gymnosperms such as pine. The wood contains resin ducts.
a fruiting body of wood-rotting fungus located on the bole of the tree.
a part of the lightning protection system used to connect conductors to each other or to metallic installations.
a multipurpose bolt clamp that is used to bond conductors, or bond a conductor to a ground terminal or tree supplemental support system.
the way in which a substance holds together.
materials that cause pest injury or death on contact.
container grown tree:
a tree grown in a container or pot.
a slow-release or slowly soluble form of fertilizer.
an agency, organization, or corporate entity with the legal authority and/or obligation to manage individual trees or tree populations.
the old-fashion cutting down of a tree within 12 in. (300mm) of the ground at regular intervals, traditionally applied to certain species such as Hazel and Sweet Chestnut that resprout to provide stakes.
a heart-shaped leaf.
a sample of wood extracted from a trunk or branch, using an increment borer tool. The resulting core can be analyzed for characteristics of growth, structure, decay, and species identification.
correct pruning cuts:
branches should be removed at their point of attachment or shortened to a lateral and all cuts should be kept as small as possible.
a layer inside the thin outer bark on young stems.
the first leaf on a seedling.
a term to describe a leaf margin with rounded teeth.
a cast or stamped connector used to connect cables in either an end-to-end, side-by-side, or a Y configuration in a lightning protection system.
Critical Root Zone (CRZ):
the portion of the root system that is the minimum necessary to maintain vitality or stability of the tree. Encroachment or damage to the critical root zone will put the tree at risk of failure.
the portion of a tree beginning at the lowest main scaffold branch extending to the top of the tree including all the branches and foliage but not including any clear stem/trunk. On younger trees, the crown may be comprised of temporary branches.
the selective removal of dead, dying, diseased, and broken branches from the tree crown.
the amount, compactness, or depth of foliage on a tree crown.
the distribution of branches relative to the trunk.
the removal of a portion of smaller branches, usually at the outer crown, to produce a uniform density of foliage around an evenly spaced branch structure. It is usually confined to broad-leaved species. Material should be removed throughout the tree and no more than 30% during one growing season.
crown lifting or crown raising:
the removal of the lowest branches. Good practice dictates crown lifting should not normally include the removal of large branches growing directly from the trunk. Crown lifting on older, mature trees should be avoided, restricted to secondary branches, or shortening of primary branches. Crown lifting is an effective method to enable access under the crown but should be restricted to less than 15% of the live crown height. Crown lifting height should be specified.
the selective reduction in height and/or spread of a tree's crown. Crown reduction should retain the main framework of the crown, a significant proportion of the leaf bearing structure, and a smaller outline. Crown reduction cuts should be as small as possible. Reductions should be specified by actual measurements. Crown reduction should not be confused with 'topping', a harmful treatment.
a named tree selection from which identical or nearly identical trees can be produced, usually by grafting, vegetative propagation, or cloning.
cultural control methods:
plant management through irrigation, raking, pruning, etc. as well as the control of vegetation through the establishment of compatible, stable, plant communities or the use of crops, pastures, parks, or other managed landscapes.
the planned interval of time between vegetation maintenance activities.
one of the molecules in DNA.
occurs when defects lower the quality of the wood.
Diameter at Breast Height is the measurement of the trunk diameter taken at 4.5 ft (1.4 m) above the flare.
a brace formed by threading a lag-thread screw rod directly into the branch, leader, or trunk, but not out through the side opposite the installation.
a manufactured wire wrap designed to form a cable termination at the end of a cable that meets the specifications of ASTM A-475 for zinc coated strand.
anchors or braces that are threaded directly into the tree but not out the side opposite the installation. Dead-end hardware includes but is not limited to: lag hooks, lag eyes, and lag-thread screw rod.
non-living branches that provide essential wildlife habitats and its management should aim to leave as much as possible by shortening or removing only those that pose a risk.
(v.) the decomposition of woody tissues by microorganisms or (n.) wood that is decomposed.
decay detection device:
a device used to assess the presence of hidden internal decay.
any tree that loses all its leaves at one time during the year, usually in autumn.
occurs when an entire tree exhibits a lack of vitality such as reduced leaf size, color, or density. decurrent: the rounded or spreading growth habit of the tree crown.
grow in loose sandy soils and are usually able to grow deeply into the soil.
injuries, growth patterns, decay, or other conditions that reduce the tree's structural strength.
the loss of leaves.
the release of seed capsules at maturity.
the study of cores and cross-sections of a tree to determine old weather patterns and growth maps that are used for dating old wood.
the process of reducing nitrates to nitrogen gases, usually in soil.
a leaf having teeth perpendicular to the margin.
severe drying out.
desired and preferred use:
the development of a product given the end-use goal, including but not limited to the highest and best use.
dicotyledon or dicots:
have two seed leaves and belong to a trees such as oaks, maples, and beeches.
occurs when the tips of branches exhibit no signs of life due to age or external influences. Dieback may progress, stabilize, or reverse as the tree adapts to its new situation.
when a cell changes its structure, such as when a parenchyma cell becomes enlarged to form a vessel, it is no longer a parenchyma cell.
trees such as maple, birch, poplar, and cherry, are angiosperms which have vessels, parenchyma, and fibers of about equal size and diameter arranged at about equal distances from each other throughout the growth increment.
trees that have male and female elements on separate plants.
direct cable installation:
consists of a single cable between two tree parts, such as two branches, two stems, or a trunk and a branch.
guides the tree to grow in a certain direction by removing live branches from other portions of the tree.
any alteration from the normal development and functioning of a tree or plant.
very high voltage electric supply lines
the taller of two leaders or the larger of identical seedlings.
the inactive growth period of a tree, usually during the coldest months of the year when there is little or no growth and leaves of deciduous trees have been shed.
an occurrence of two separate bands of heartwood that form just below the union of a forked tree trunk.
shortening branches by pruning off the end back to a lateral branch which is at least 1/3 of the diameter of the removed branch. Drop crotching usually refers to a poor pruning practice.
a method of tying the root ball of a balled-and-burlapped tree for moving.
a simple, fleshy fruit, with a single seed such as in a peach or cherry.
duty of care:
the legal obligation that requires an individual to apply reasonable actions when performing tasks that may potentially harm others.
a tree's response to consistent strong winds that reduces their above ground growth.
dynamic cable system:
any of several cabling systems that utilize nonrigid materials for tree support systems.
the study of the relationships between organisms and other elements of their environment.
the pest population level at which the cost of inaction is less than the cost of action. ecosystem: many cells create a tissue, many tissues create an organ, many organs create an organism, and many organisms create an ecosystem.
these mycorrhizae infect the outermost fungal cells and are most common in conifer, beech, oak, and hickory forests.
any material through which an electrical current can flow.
the relative opposition to the flow of electrical current, measured in ohms. Material such as copper has low resistance and is therefore a good conductor.
a young tree in a seed before the start of rapid growth.
holes in the bark created by insects leaving the plant to complete their life-cycle. Also called exit holes.
the inner layer of cortex in roots.
an electrical conductor through which electrical current is flowing.
a leaf margin without teeth.
a complex protein that speeds up certain chemical reactions.
the outer layer of cells on all parts of a tree except the roots.
the total removal of a species from a particular area.
the wearing away of the land by the movement of water, wind, or ice.
in felling operations, the direction for chain saw operator to move while tree is falling.
the combination of pruning, supporting, and training branches to orient a tree to one plane, often used against a wall.
the 17 minerals essential for the growth and development of trees.
the point after planting when a tree's root system has grown sufficiently into the surrounding soils to support shoot growth and anchor the tree.
the gaseous plant hormone that triggers fruit ripening.
1) the process of comparing the current or predictable pest population to the action threshold, to determine the need for treatment or 2) the process of assessing the results of the IPM program.
occurs when rainfall on the leaves and bark vaporizes after a storm
the loss of water by evaporation from the soil surface and transpiration by plants.
any tree that retains its leaves for more than one growing season.
tree growth habit characterized by a central leader and a pyramidal crown.
peeling off bark in shreds or layers.
not native to a region.
a drop-forged, closed-eye bolt used in cabling.
a closed-eye termination formed into rope or common grade cable by bending it back on itself and winding each rope strand or wire around the rope or cable a minimum of two complete turns.
may be used above ground as a plant "container" or in the ground as an "in-ground growing bag".
the notch made to help control the direction of fall of trees or branches being removed.
a structure or equipment used to deliver or provide protection for the delivery of an essential service, such as electricity or communications.
the breakage of branches or loss of mechanical support by the tree's root system.
a device installed in a tree to hold ropes during climbing or rigging.
an attachment to secure a lightning protection conductor to a tree.
a high-priority electric distribution supply line, generally 12,000 to 34,500 volts.
dropping or cutting down a tree.
the application of fertilizer to the soil within the tree's rooting area, to promote tree growth. This will only be effective if nutrient deficiency is confirmed.
a substance containing one or more nutrients to be used by a tree or surrounding soil to supplement the supply of essential elements.
the composition of a fertilizer expressed as a percentage by weight of total nitrogen (N), available phosphoric acid (P2O5), soluble potash (K2O), and other essential nutrients listed on the bag.
the ratio of total nitrogen (N), available phosphoric acid (P2O5), and soluble potash (K2O); for example, the ratio of a 30-10-10 fertilizer is 3:1:1.
many lateral roots that are shallow, wide spreading, numerous, and grow horizontally to stabilize a tree.
the maximum soil moisture content following the drainage of water due to the force of gravity.
soil, sand, gravel, rocks or other material placed over the existing soil surface to raise the finished grade to some specified level.
the cut that completes the removal of a branch.
bacteria form nitrogen fixing nodules on the roots of many trees in the legume family. The nodules form nitrate or ammonium ions which can be absorbed by the tree.
the symptom in which leaves on a branch wilt and may ultimately turn yellow or brown without
falling from the branch.
the transition zone where the trunk flares out to meet the buttress, main, or structural roots. It was also called trunk flare, root flare, or first order lateral roots, but these terms are falling out of favor.
floral leaves grouped together on as stem for sexual reproduction in angiosperms.
flush cut pruning:
cutting flush with the trunk. This is not an acceptable practice.
live leaves or needles of the tree, the tree part primarily responsible for photosynthesis.
a simple dry fruit that splits along one side.
objects including, but not limited to miscellaneous metal and concrete objects and glass insulators that a tree has grown around after many years of disuse.
systems where trees and many other communities of organisms are connected in ways that ensure high quality survival for all.
hyphae from mycorrhizae on one tree that can connect with hyphae from another tree, even of a different species.
the management of forests.
the very weak branch union of two identical stems.
wood shavings produced by insects boring into a tree.
climbing a tree without being secured by a climbing rope.
a gravel filled trench used to drain water from the soil.
the leaf of a palm.
a vertical split in the wood of a tree, caused by internal stresses and low temperatures.
ripened ovaries and their attached parts.
any plant without roots, stems, or leaves and is unable to make its own food, excluding bacteria.
when a fungus may colonize tissues of a tree and form beneficial relationships with the roots. Their microscopic cells are often joined to form long tubes. The fruiting body is spore bearing. As fungi decompose matter they release carbon dioxide and return nitrogenous compounds to the soil.
the pointed, spur portion of a climbing spike.
abnormal swelling of plant tissues caused by various insects.
the complex of tunnels created by insects in trees for feeding and shelter.
a taxonomic category ranking below a family and above a species or a group of species.
a substance within a chromosome that determines hereditary characteristics.
Geographic Information System (GIS):
any system used for capturing, storing, analyzing, and managing data and associated attributes which are spatially referenced to the earth.
a synthetic fabric used in landscape construction as a barrier under mulch or pavement to reduce weed germination. It is becoming less popular because it also blocks the flow of water through the soil.
a growth induced by gravity. It makes roots grow down and stems grow up.
the beginning of growth in a seed, spore, or bud.
a group of plant hormones involved in cell elongation.
Global Positioning System (GPS):
a series of satellites that transmit precise microwave signals, that enables a receiver to determine its exact location, speed, direction, and time anywhere on the earth.
a simple sugar manufactured in a green leaf.
to join together tissues from the same or different plants in order to create desirable characteristics.
the junction between root stock and scion wood, evident by a thickening of the trunk at the union, not to be confused with the flare.
household wastewater from bathroom sinks, showers, bathtubs, and clothes washers. Suitable for watering landscapes and trees.
the living plants and natural materials within developed areas.
a mulch composed of green organic matter and not fully composted.
the rise in temperature caused by gases or materials suspended in the atmosphere that trap energy from the sun.
an 8 ft (240 cm) long copper and steel rod driven into the ground as part of a lightning protection system.
the low-growing plants that require minimal maintenance, used in landscaping instead of turf or mulch.
in utility arboriculture, the distance between live or energized conductors and the ground.
water naturally stored underground in aquifers and saturated soil.
replenishment of both groundwater levels and normal weather stream flows.
trees and shrubs may be grown in these bags in the field. See "fabric bags".
a chemical that regulates enzymes and the growth of a tree.
the shape, growth rate, mature size, and branching structure of a tree without pruning.
the incremental of growth added as new wood each growing season over existing wood. This is seen as growth rings in cross-sections of wood.
a pair of specialized cells that regulate the opening and closing of a stomate.
the installation of a steel cable or a synthetic-fiber cable system between a tree and an external anchor to provide temporary supplemental support.
softwood trees such as conifers, which have naked seeds and resin ducts.
a place where any organism can live.
a broken branch that is hanging in a tree.
a protective hat made of a rigid material that must be worn when climbing and working on trees.
plant tissue that is acclimated to the cold or a new environment.
the genetically determined ability of a plant to survive low temperatures.
nearly impervious compacted soil.
the built infrastructure such as pavement, outdoor furniture, gutters, storm drains, walls, and footings.
trees that lose their leaves in autumn. It also refers to the wood produced by these trees. Hardwoods are the predominant type of tree in the deciduous forest.
harvesting or tree removal:
the process of removing trees and creating lumber products from a rural, urban, or community forests.
a situation or condition that may result in personal injury, property damage, or disruption of human activities.
the process of managing, reducing, or eliminating an identified hazard.
1) cutting a currently growing shoot, back to a bud. 2) cutting an older branch or stem back to a stub in order to meet a defined structural objective. 3) cutting an older branch or stem back to a lateral branch not large enough to assume apical dominance. Heading is not an acceptable pruning practice, unless specified as "shearing".
any of several types of fungal decay of tree heartwood.
wood that provides chemical defense against decay-causing organisms and continues to provide structural strength to the trunk.
when temperatures are over 86° F (30° C) and is the point at which plants begin suffering physiological damage from heat.
heat island effect:
an urban area that is warmer than its surrounding rural areas due to urban activities.
the vertical distance of a tree between the flare and the top of the stem.
any chemical that kills plants or inhibits their growth and is intended for weed control.
highest and best use:
the use that garners the greatest economic, social, and environmental return given the quality and quantity of the resource and the best use acknowledging practical economic, societal, and environmental realities.
high risk tree:
a tree that can not be practically treated against failure because of defects and potential targets.
a strip of uncut wood fibers created between the face cut and the back cut that helps control direction in tree felling.
hook-and-blade type pruning tool (by-pass pruner):
a pruning tool that has a sharp curved blade that overlaps a supporting hook, in contrast to an anvil-type pruning tool.
horizontal ground system:
the ground terminal of a lightening protection system composed of ground rods or copper ground plates that are not fully driven or installed in the ground due to site conditions.
a product produced in one part of a tree and transported to another part where it controls a process.
the cultivation of fruits, vegetables and ornamental plants.
a highly refined petroleum oils that may be applied to plants to smother certain insects.
a living organism from which a parasite obtains nutrition.
slow decomposition reactions in soils. Humic and fulvic acids buffer pH swings in the soil.
the decomposing organic materials in soil which contain humic acids.
a plant resulting from a cross between two or more other plants.
hydraulic soil excavation:
the removal of soil using pressurized water to minimize root damage.
crystalline polymers which absorb water.
can absorb toxins to a greater concentration than the soil in which it is growing.
the vegetative structures of fungi that look like tubes.
the uptake of water by seeds.
a surface that does not allow for infiltration of liquids.
a capsule or other device permanently inserted into the xylem to treat diseases and pests.
the bark embedded in the union between a branch and the trunk or between two or more stems that prevents the formation of a normal branch bark ridge. Included bark is unacceptable.
a device used to take core samples from trees to determine age or detect problems.
a plant specifically used to signal a need for watering.
naturally occurring, not introduced.
capable of being spread from plants to other plants.
the presence of a pest population.
the speed at which water penetrates the soil.
a flower cluster.
forcing a liquid substance into a tree or soil.
a physiological disruption that harms the tree.
mycorrhizae that are introduced into the soil to improve growth.
a substance not containing carbon.
a natural phenomenon in which trunks, branches or roots of two trees grow together.
a soap-based pesticide.
any chemical that kills insects.
a stage of growth between molts in the development of insect larvae.
integrated pest management (IPM):
an approach for managing pests that assesses the pest situation, considers options, and then implements management strategies, including biological, cultural, mechanical, physical, and/or chemical tactics based on effectiveness, environmental impact, site characteristics, safety, economics, sustainability, client expectations, and preferences.
integrated vegetation management (IVM):
a system of managing tree communities in which vegetation is identified, action thresholds are considered, control methods are evaluated, and the selected control is implemented to achieve a specific objective based on effectiveness, environmental impact, site characteristics, safety, security, and economics.
the amount of rainfall temporarily held on tree leaves, bark, and stem surfaces.
crossing, rubbing, or upright branches that have the potential to damage tree structure and health.
organisms not native to a region.
the intentional release of a non-native species within a landscape.
a cut located between lateral branches or buds. This is not an acceptable practice.
an organism that if removed from its native community or cultivation, has the ability to overspread other habitats and is likely to cause economic or environmental harm.
an individual who possesses necessary credentials, experience and has supervisory oversight for developing IPM policy and programs.
an individual who possesses necessary credentials and experience for implementing IPM programs.
IPM specialist trainee:
an individual undergoing IPM training to obtain experience, competency and credentials and is under the supervision of an arborist, IPM manager or IPM specialist.
the smell in a forest containing pine trees.
a street tree management tool developed by the USDA Forest Service that uses the tree inventory data to quantify the dollar value of annual environmental and aesthetic benefits.
under cuts made to prevent bark tearing from a branch or trunk section being removed.
a pest that frequently results in unacceptable damage and typically requires treatment.
1) a plant that frequently experiences unacceptable pest damage or 2) a plant of value.
the sudden, sometimes violent and uncontrolled, backward or upward movement of a chain saw.
a main root that is sharply bent. Kinked roots are unacceptable.
a cut or broken branch, sprout branch, including live or dead material, protruding or depressed, but with exposed sound or rotted wood.
a lag-thread, drop-forged, closed-eye anchor used in tree cabling.
lag hook or J-hook:
a lag-thread, J-shaped anchor used in tree cabling.
a coarse screw thread designed for securing into wood and used in tree cabling.
anchors or braces with lag-threads used in tree cabling. Lag-thread hardware includes but is not limited to: lag eyes, lag hooks, hardware, and lag-thread screw rod.
lag-thread screw rod:
a lag-thread, steel rod, used in tree cabling for dead-end and through-brace installations.
land disturbance permit or development permit or vegetation removal permit:
issued by the City that regulates and authorizes the commencement of development on a given tract of land.
the predetermined area where cut branches and wood will be lowered from a tree.
areas of land that are distinguished by differences in land-forms, vegetation, land use, and aesthetic characteristics.
the art of arranging or modifying landscape features of urban, suburban, and rural areas for aesthetic or practical reasons with priority on health, safety, and welfare of the public.
a currently registered individual engaged in the profession of landscape architecture who, through experience, education, and training possesses the competence to design, arrange, or modify landscape features for aesthetic and practical reasons with priority on health, safety, and welfare of the public.
the purpose or intended use of a tree in the landscape such as for shade, aesthetics, or screening.
identifies areas of tree preservation and methods of tree protection within the no-build zone, as well as all areas of planting, including the common and botanical names of the proposed species, the number of plants of each species, the size of all plant materials, the location of all plant materials, and any unique features of the plant materials.
a short rope equipped with carabiners, snaps, etc. to be used for temporarily securing the climber. larvae: the immature life stage of an insect between the egg and the pupa.
an arrangement of rope used to hold two objects together.
a bud held in dormancy for more than one year by hormones originating from the terminal bud.
a shoot or stem growing out from the side of a parent branch or stem.
a root that arises by cell division in the pericycle of the parent root and then penetrates the cortex and epidermis.
the tip of the leaf blade.
a point of attachment of a leaf petiole to a stem.
the bottom part of the leaf blade.
irregularly shaped areas of disease on plant foliage.
the outer edge of the leaf blade.
a scar left on the twig after a leaf is shed.
the patches of disease or damage on plant foliage.
a separate part of a compound leaf blade.
a departure of a stem from vertical, beginning at the base of the trunk.
and needles are organs uniquely constructed for trapping the energy from the sun. As leaves grow and mature, chlorophyll is formed in the living cells. As chlorophyll is formed the first time, the elements must come from stored reserves. As leaves die, chlorophyll is no longer produced, and the leaf takes on the colors of the other pigments present. Leaves begin to die, the abscission layer forms and then falls from the tree.
LEED (Leadership in Energy and Environmental Design):
the green building rating system developed by the U.S. Green Building Council (USGBC) to provide standards for environmentally sustainable construction and building management practices.
any clothing or device to protect the legs from various injuries, worn over the legs when operating a chain saw.
structures in bark that permit the passage of gas inward and outward.
something for which one is responsible.
the series of stages in the life of an organism.
one of multiple phases in the growth and development of an organism.
high amounts of the natural "cement" called lignin is deposited within the cellulose strands in the cell walls. This makes the cell walls very tough which is a unique feature of trees as well as wood.
the cutting off the side branches of a felled tree.
limitied visual inspection:
a visual assessment from a specified perspective such as by foot or vehicle.
the removal or an excessive number of inner, lateral branches from parent branches, leaving leaves at the end of the branch. This is not an acceptable pruning practice.
The ideal soil texture classification based on a certain ratio of sand, silt, and clay.
leaf segments that project outward.
in a street tree inventory, this rates the position of a tree based on land use of the site and the value of the tree.
a method for producing saw logs that may be processed into lumber products.
a synthetic fiber termination that serves as an anchor in a cabling operation.
a pruning tool with two long handles used to cut woody stems.
lopping and topping:
lopping refers to the removal of large side branches and topping refers to the removal of large portions of the crown of the tree. Often used to describe crude, heavy-handed or inappropriate pruning.
low risk tree:
a tree with minor visible structural defects or wounds in areas with moderate to low public access.
a fine screw thread designed for tree cabling fittings such as hardware nuts.
a machine-thread steel rod used for tree cabling and bracing installation.
a trunk injection technique that requires a relatively large-diameter hole in the trunk.
nutrients required in relatively large amounts by trees, such as Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg), and Sulfur (S).
the lightning protection system's copper conductor starting at the air terminal and running down the trunk to the ground rod, that is buried mostly in the ground.
the planned length of time between routine vegetation management activities.
a number used to locate a tree with X and Y coordinates generated by GPS.
the price an asset would fetch in the marketplace.
the retaining of dead leaves and other tree parts over winter.
mechanical control methods:
any physical activity that inhibits unwanted tree growth using saws and pruners.
a utility pruning technique where large-scale power equipment is used to cut back branches.
a mixture of two or more ingredients such as soil, peat, perlite, etc. in which a containerized tree has been grown.
groups of cells that have the ability to divide and produce more cells that eventually differentiate or mature to form all parts of the tree.
nutrients required in relatively small amounts by trees such as, Iron (Fe), Manganese (Mn), Zinc (Zn), Copper (Cu), Chlorine (Cl), Nickel (Ni), Molybdenum (Mo), and Boron (B).
milled urban forest products:
solid wood products derived from a saw log and manufactured at a sawmill.
a chemical that kills mites.
the process of diminishing the risk of tree failure by reducing or alleviating unfavorable conditions in very high to moderate risk trees.
normal cell division, involving splitting the nucleus and duplication of chromosomes.
moderate risk tree:
a tree may have defects that are cost effectively treated.
distinctly filamentous, microscopic or submicroscopic fungi that breakdown soil organic matter.
the smallest portion of a compound. The six molecules that dominate life are glucose, water, carbon dioxide, oxygen, ammonia, and carbonic acid.
a systematic inspection of the managed landscapes conducted at regular intervals to determine the types of pests, their numbers, the amount of damage caused, beneficial organisms, and the effectiveness of treatment methods.
trees that have a single cotyledon or one leaf seed such as a palm. They are in the monocotyledons group.
a tree population dominated by one single or very few species.
the mixture of soil colloids mixed with root and microbial gels on the surface of roots.
any material applied to the soil surface to: protect the soil, deter erosion, moderate temperature, conserve moisture, inhibit weeds, and improve soil structure.
multiple ground system:
consists of a ground terminal composed of two or more ground rods or copper ground plates in a lightening protection system.
a mass of hyphae forming the body of a fungus.
organs made up of tree and fungus tissues. They facilitate the absorption of nutrients dissolved in water. Hyphae from mycorrhizae on one tree can connect with mycorrhizae from another tree of a different species.
plant movements that occur in response to environmental stimuli.
the natural death of branches on the stem of a tree from such causes as decay, deficiency of light and water, or damage by snow, ice, and wind.
natural target pruning:
a pruning technique in which only branch tissue is removed, with the cut placed just beyond the branch collar.
the death of tissues caused by a nutrient deficiency or the activities of a pathogen.
the process of changing ammonium salts into nitrates that are acceptable for tree growth.
positions on a stem where leaves form. The three basic nodal positions are alternate; opposite; and whorled.
organs of microbes on roots, mostly bacteria, actinorhizae, or cyanobacteria, and tree tissues.
non-milled urban forest products:
products that are typically of lower economic value, including firewood, poles, pulpwood, biomass fuel including pellets, chips, mulch, sawdust, engineered lumber, and wood fiber.
methods used to control vegetation within a prescribed area without regard to retaining compatible vegetation.
non-selective treatments or cover sprays:
methods used to manage pests without consideration of an IPM approach.
an organism that is not intentionally targeted by a pest management strategy.
trees grown in or obtained from a nursery.
a dry, one seeded fruit produced from a compound ovary.
elements or compounds required for growth, reproduction, and development of a tree.
the circadian rhythm associated with daylight and temperature changes.
occur when there are two buds or leaves at a node.
a group of tissues that perform a specific function. A tree has four major organs - roots, stem, leaves, and flowers.
include carbon containing carbohydrates, proteins, fats, and other compounds of plants and animals.
derived from the growth and death of living organisms and are the organic components of soil.
a pesticide made from naturally occurring ingredients. Organizations and agencies certify materials as meeting their requirements for use of the term "organic".
the diffusion of water through a deferentially permeable membrane. This means water will move in two directions through the membrane.
water flowing through a permeable membrane in the direction of a higher salt concentration.
any tree or stand of trees that has passed the age of maturity where the rate of growth has diminished and trees are weakened.
the depositing of eggs by insects.
covering pruning cuts or other wounds with a paint or sealant, is considered harmful.
palms are monocots, not trees, but can be called tropical trees. They have one seed leaf and an apical meristem. Palms do not increase in circumference until after trunk tissues mature. Roots grow from meristematic regions at the base of the trunk. The apical meristem forms fronds and fruit.
the movement of leaves throughout the day so that they are always orientated to avoid the sun.
the specified criteria used to determine which trees are suitable for a specific urban forest product or by-product.
an organism living in or on another living organism (host) from which it derives nourishment to the detriment of the host.
thin-walled cells that contain living substances.
parent branch or stem:
a tree trunk or prominent branch from which shoots or stems grow.
the stem on a flower
the removal of only the dead palm fronds at the point they make contact with the trunk, without damaging living trunk tissue.
the act of bending, rounding or flattening the fastening end(s) of cabling-hardware for the purpose of preventing a nut from "backing-off."
a flower having both stamens and pistils.
consists of parenchyma cells just inside of the endodermis, forming the rest of the stele other than the xylem and phloem.
periderm or outer bark:
mostly dead cells that form the protective covering of trees. These cells are lined with a fatty substance called suberin or cork.
living organisms including animal, insect, mite, disease, nematode, or invasive species that can cause injury.
the stalk of a leaf or frond.
pH (potential Hydrogen):
a measure of the hydrogen ion concentration in soil and is used to express the acidity or alkalinity of a solution on a scale of 0 to 14, where less than 7 represents acidity, 7 neutrality, and more than 7 alkalinity.
a cork cambium or the phellogen portion of the outer bark.
also known as the bark cambium, this is the outer most part of the symplast. When the phellogen ruptures it forms fissures.
the timing of natural processes: flushing, reproduction, wood formation, energy storage, shedding, and dormancy. A qualified arborist should make treatment decisions based on this information.
also called inner bark and are tissues that transport energy containing substances made in leaves and are moved toward non-woody absorbing roots. They are located just outside the cambium zone and inside the phellogen and the outer bark.
chlorophyll traps the light energy of the sun to run processes that uses carbon dioxide and water to form glucose. Oxygen is given off in the process of glucose formation. The energy in the sugar is a building block for many other compounds.
refers to growth that is stimulated by light, when plants in the dark, bend toward the light.
physical / mechanical management method:
the physical removal of pest by the use of equipment.
the science of the functions and activities of living organisms.
the essential oils released by trees and plants to defend against insects, animals, and decomposition.
the removal of nitrates, phosphates, and other contaminates from the soil and water by trees. For more information see Phytoremediation in Topic #15.
includes the construction of wetlands, bioswales, rain gardens, bioretention basins, and the use of phytoremediation to prevent ecological problems before they actually occur.
roots destined to become woody roots from the moment they start to grow.
the central organ of a flower and contains the ovary, style, and stigma.
a tissue in the center of trunks, branches, and twigs, made up of large cells.
the extraction of trees from a landscape as part of a management plan, hazard abatement, or other planned strategy.
a vacant tree planting site indicated in the tree inventory.
a cylinder of medium in which a trees is grown as a seedling or rooted cutting.
pneumatic soil excavation:
the removal of soil using pressurized air.
roots found on some trees in swampy areas that grow above the water line.
the initial removal of the top of a young tree at a prescribed height to encourage multi stem branching from that point. It is traditionally used for fodder, firewood, or poles. Once started, it should be repeated on a cyclical basis always retaining the initial pollard point.
an organism that preys on another organism.
trees growing on privately owned property and legally maintained by the land-owner.
installation of a rigid support placed between a trunk or branch and the ground.
the multiplication by any process of natural reproduction from the parent stock.
the roots produced on "suckers" or adventitious woody shoots.
grow downward from branches and from meristematic points.
a living substance in the center of a parenchyma cell.
carefully removing tree parts to meet specific goals and objectives.
the sound of wind in the trees and rustling of leaves.
trees growing on publicly owned property and legally maintained by the controlling authority.
an individual, who by possession of a recognized degree, certification, or professional standing in the profession of arboriculture and through experience, education, and related training, is familiar with the equipment and hazards involved in arboricultural operations and who has demonstrated ability in the performance of the special techniques involved in the management of trees and other woody plants.
qualified line-clearance arborist:
an individual who, through related training and on the job experience, is familiar with the equipment and hazards in line clearance and has demonstrated the ability to perform the special techniques involved. This individual may or may not be current employed by a line clearance contractor.
qualified line-clearance arborist trainee:
an individual undergoing related training and on the job experience, is familiar with the equipment and hazards in line clearance and has demonstrated the ability to perform the special techniques involved. This individual shall be under the direct supervision of a qualified line clearance arborist.
an individual possessing skills, experience, training, education, certificates, degrees, registration, certification, or licensing as needed to perform job tasks.
a fertilizer with less than 50 percent (50%) water-insoluble nitrogen (WIN) and is immediately available to the tree.
the parenchyma cells that run in a direction perpendicular to the trunk.
removing and replacing soil in trenches that begin between buttress roots.
the primary root in a seed and is the first root to emerge during germination.
the selective pruning required to provide vertical clearance.
as trees sway, reaction wood forms in places to optimize the strength of the trunk and branches. Compression wood forms on the lower side of the lean in conifers. Tension wood forms on the upper side of the lean in woody angiosperms and gymnosperms.
a barrier zone is a chemical boundary within the wood present at the time of wounding which resist the spread of pathogens.
the collection, sorting, and preparing the products of urban and community tree harvesting as a means to obtain the highest and best use and avoid waste.
This is a designation by the U.S. EPA that includes using pesticides with a low impact on human health, low toxicity to non-target organisms, low potential of ground water contamination, low use rates, low pest resistance potential, and compatibility with IPM practices.
selective pruning to decrease the height and spread of the crown, usually to provide clearance for utility lines.
region of elongation:
where all increases in root length occur.
region of root hairs or differentiation:
the area where root cells develop a more mature form and are differentiated into the epidermis and cortex.
the extraction of part of or the entirety of one or more trees through felling, trimming, or other maintenance activities.
a gear-driven drilling instrument which inserts a three-millimeter-diameter probe into a tree and graphically or digitally records resistance to the probe for the purpose of detecting decay and defects.
resource / site assessment:
a systematic determination of the landscape parameters, tree species, pest populations, key trees, pests, and site conditions.
the process of releasing the energy. Respiration in roots produces carbon dioxide and water which can become carbonic acid. Respiration in the presence of molecular oxygen gives off carbon dioxide and water.
the selective pruning necessary to improve the structure, form, and appearance of trees that have been severely headed, vandalized, or damaged.
a form of reduction intended to encourage development of lower shoots and emulate the natural process of tree aging.
the absorbing root-soil interface. The zone is about 1/32 in. (1 mm) width, surrounding the epidermis of living root hairs and the boundary cells of mycorrhizae as well as hyphae growing out from some mycorrhizae. A constantly changing mix of organisms inhabit the rhizosphere including bacteria, fungi, actinomycetes, protozoa, slime mold, algae, nematodes, enchytraeid worms, earthworms, millipedes, centipedes, insects, mites, snails, small animals and soil viruses.
a strip of land usually owned by a public entity, over which transportation and utilities are built.
conditions on a ROW in need of reclaiming requires non-selective methods of mowing or broadcast application of herbicides to deal with undesirable vegetation, and utility facilities that are inaccessible.
ring porous wood:
wood such as, oak, elm, chestnut and black locust, are angiosperms that have large diameter vessels in the first portion of the growth increment and vessels of smaller diameter later in the growth increment.
trees along the edge of streams that provide a buffer during storm events. The buffer vegetation removes nitrogen and phosphorus leached from adjacent forest, turf, or agricultural lands and provides stability to the stream banks. It also provides shade that cools the stream water temperature and provides aquatic and wildlife habitat for many species, while reducing stream velocity and downstream flooding.
the descending axis of a tree that serves to anchor the tree and absorb and conduct water and mineral nutrients.
the ball of earth or growing medium containing the roots of a nursery tree.
a device designed to direct root growth down and away from the soil surface.
the mass of cells covering the apical meristem of a root.
an underground system that increases soil volume or a system that is used to direct root growth to a favorable environment.
the point where the roots separate from each other. The root collar is below the flare.
root collar examination (RCX):
the process of exposing and assessing the root collar, often including excavation of mulch, soil, roots, and other material.
composed of loosely packed round tissue cells with large diameters.
the area where buttress roots divide.
severing roots non-selectively.
roots that encircle all or a portion of a trunk and contacts the trunk or a buttress root. This contact impedes development and circulation of the roots and inhibits the health and stability of the tree and therefore should be removed.
the extension of a single epidermal cell. Root hairs absorb water and elements dissolved in it. Root hairs are organs that grow within days when water, temperate, and soluble essential elements are at optimum levels. Root hairs are not common on most mature trees.
legumes and a few other plants produce root nodules, which contain bacteria that can "fix" nitrogen into the nitrate form.
a mix of buttress roots, absorbing roots, and soil and is responsible for holding the tree erect.
pruning back of roots (similar to the pruning back of branches) has the ability to affect tree stability so it is advisable to seek professional advice prior to attempting root pruning.
occurs soon after transplanting and refers to the replacement of roots that were lost during the digging process and are being replaced at the tips of the cut roots.
lateral roots that are visible above grade.
grow from meristematic points. Roots that do not grow from buds.
root stock or under-stock:
the flare, trunk, and roots on which another tree has been budded or grafted.
the portion of the tree containing the root organs, including buttress roots, transport roots, fine absorbing roots, and all underground parts of the tree.
the volume of soil containing the roots of a tree.
wood in its natural state as felled, with or without bark. It may be round, split, roughly squared or in other forms.
the osmotic potential ratio of a fertilizer compared to sodium nitrate, based on the relative value of 100. The higher the salt index, the more likely that tree damage will occur.
a two seeded fruit with a wing-like growth. Maple and elm trees produce samara seeds.
about 65% of the sugars in maple sap are sucrose. Sucrose is a disaccharide made up of glucose and fructose.
major functions: 1) transport; 2) storage; 3) mechanical support; 4) protection and defense. The living cells of sapwood store energy reserves.
most microorganisms that live on bark are saprophytes and cause the tree no injury.
a log meeting regional standards of diameter, length, and freedom from defect, including a minimum 6 ft (2 m) length and 6 in (15 cm) trim and a minimum top diameter inside bark of 6 in (15 cm) for softwoods and 8 in (20 cm) for hardwoods.
large main branches that form the main structure of the crown.
any process of breaking, scratching, or altering the seed coat through mechanical, chemical, or thermal methods, such as freezing to make the seed coat permeable to water and oxygen.
scope of work:
a document that defines the work activities, deliverables, and timeline a vendor must execute in performance of specified work for a client.
a treatment to a wound. However, scribing is no longer recommended. It is best to just remove the loose inner and outer bark and let the tree close the wound.
a crack or split running with the grain for part of, or the full length of a log.
relating to, occurring in, or varying with a particular season.
nutrients required in moderate amounts by trees , Calcium (Ca) and Magnesium (Mg).
do not buy or sell trees that have flush cut branches, tops removed, pruning cuts that leave long branch stubs or leader stubs, trunk covered with some wrapping, cracks, cankers, and wounds.
methods used to target specific vegetation within a prescribed area while retaining compatible vegetation, using an IPM approach.
the process of aging, decline and death of a tree.
outer structures of a flower that enclose the other flower parts in the bud.
a leaf lacking a petiole or a flower lacking a pedicel.
a tree with many significant defects in the trunk, crown, or root zone.
denotes a mandatory requirement.
roots grow in heavy soils so the roots do not grow deeply.
a mature tree can maintain a prime space position with a larger spreading crown in the forest, so long as shedding regulates the increasing dynamic mass-wood with living cells.
shredded wood resulting from the manufacture of shingles. Used to wrap bare root trees.
denotes an advisory recommendation.
a woody plant similar to a tree except it is usually several-stemmed and smaller than a tree.
the soil area around a tree in a sidewalk. Also called the tree grate area, planting bed, tree surround or sidewalk tree saucer.
single ground rod:
the ground terminal of a lightening protection system composed of one ground rod.
the number assigned to a tree at a given address in the tree inventory.
a fertilizer with at least 50% water-insoluble nitrogen.
a standing tree at least 20 ft (6 m) tall that has decayed to the point where most of the branches have fallen. The snag is used as a foraging and nesting site by birds.
refers to cone-bearing trees with needles or scale-like leaves. It also refers to the wood produced by these trees. Softwoods are the predominant tree type in coniferous forests.
a substance made up of sands, silts, clays, decaying organic matter, air, water and an enormous number of living organisms. Soils contain loose material of weathered rock and minerals in association with many other organisms in the soil such as bacteria, insects, worms, amoebae, nematodes, and small animals.
filamentous or single-celled photo-autotrophic microorganisms found in wet soil.
any material added to soil to alter its composition and structure, such as sand, fertilizer, or organic matter.
any physical or chemical altering of soil to improve conditions like pH, drainage or aeration.
an arrangement of soil particles into classifications according to how soil particles clump or bind together, creating voids between them.
the volume of soil available to trees and other woody plants for root development.
the lowest category of taxonomic classification, ranking below a genus. Abbreviation sp.
a detailed, measurable plan for performing a work activity or providing a product, usually a written document.
any tree that is considered worthy of occupying a focal point in a landscape based on size, form, species, beauty, historical significance or any other feature that is considered significant. The worthiness can be determined by an arborist, historian, landscape architect, or any other person who can show that the tree is worthy of special recognition.
a reproductive cell that develops into a fungus or small plant.
abbreviation for more than one species. (sp.: single but unidentified species)
the horizontal width of the crown of a tree.
in cross section, early wood or spring wood is the xylem which has become lignified in the spring of the current year. It is light in color and fast growing wood that appears between the "rings" in the wood.
similar to branches, but do not have a branch collar, are weekly attached, and grow from a meristematic point.
to support a tree in a new location after failure.
an underground tree support system that holds the roots tightly to the soil.
stabilize trees with broad, belt-like, flexible material that will not injure the bark, but allow trees grow and sway. Remove material no later than after 1 year. Only stake if tree will blow over in mild wind. Avoid placing the device in crotches. Preferred method is to stabilize the root ball to the soil.
the part of a flower that contains the anther and filament or stalk.
trees change glucose to starch and the store starch in woody roots and in living parenchyma cells. When trees need energy the starch is transformed back to glucose.
a woody structure with buds, foliage, and other stems, also called leader or central leader.
a circling, bent, or straight root that touches or rests on the flare and becomes a permanent root. It is also called a girdling root. Stem-girdling roots are unacceptable.
a minute opening, bordered by guard cells in the epidermis of a leaf, through which gases pass.
a tree growing within a right-of-way.
street tree management plan:
a plan to evaluate the tree resources along the streets and public ways in a community, develop goals for health and viability of these trees, prescribe strategies for tree management, and monitor progress.
the adverse alteration of tree health by abiotic or biotic factors that result in strain or deformation.
these roots grow vertically downward until they encounter an obstacle or soil with insufficient oxygen for growth.
the minor pruning during the early years of a tree's growth to establish the desired form and/or to correct defects or weaknesses that may affect structure in later life.
large, woody, tree roots that anchor and support the trunk and crown. Roots characterized by secondary thickening and relatively large diameter.
structurally weak or hazard tree:
a tree that is weak structurally, but does not pose a hazard because of the lack of a target but it does have the likelihood of failure.
an undesirable short length of a branch remaining after a break or incorrect pruning cut is made. It is also a tree less than 20 ft. (6 m.) tall that has decayed to the point where most of the branches have fallen.
the roots, flare, and remainder of the trunk after a tree has been removed. Noting a stump on the inventory indicates the stump should be removed.
the outer bark or phellem contains suberin or cork. Suberin is a material that coats the inside walls of the outer bark and waterproofs the cells. Suberin gives bark a corky characteristic.
used by microbiologists to indicate the food source for the organism. The substrate might be decomposing organic matter or sugars provided by roots of a tree in the case of mycorrhizal fungi.
the application of dry or liquid fertilizer below the soil surface.
shoots that originate from buds on the root systems, that grow into new full size trees genetically identical to the parent.
a disaccharide made up of glucose and fructose. About 65% of the sugars in maple sap are sucrose.
summer branch drop:
a process in which trees shed whole branches in response to an unknown stress.
late wood and is the xylem which has become lignified in the summer. It is the last wood to be formed in the current growth increment. Free water moves only in current summer wood. It is the darker and the slower growing wood that appear as "rings" in the wood.
supplemental support system:
a system designed to provide additional support or limit movement of a tree.
the application of dry or liquid fertilizer to the soil surface, mulch or ground cover.
requires a use that balances economic, environmental, and social values in perpetuity without depleting the resource.
a sleeve-type fitting used to terminate a wire rope or cable.
the gradual curvature along the length of a log that may decrease the potential volume and quality of lumber.
the process when different species live together for mutual enhancement and the energy transfer increases the benefit of a part, or the entire system of the donor, or host, and increases the order of the receiver, or pathogen.
the network of highly ordered, connected living axial and radial parenchyma cells in sapwood and inner bark. The symplast stores energy reserves. The parenchyma, which have small cell wall openings that act as tunnels where the protoplasm of one cell connects with the protoplasm of adjoining cells.
when the benefits are greater than the sum of the parts, the association is called synergistic. These are infections that result in benefits to all parts.
the thickening of a trunk or branch toward its base.
roots that grow downward in search of water and nutrients.
people or property that could be injured or damaged by the failure of a tree or tree parts.
pest management procedures that focus on a host tree and targeted pest.
something tightened to the point of eliminating visible slack.
the science of classifying and naming organisms in established categories. The name is binomial meaning two names, a genus and a species.
a small branch that is temporarily retained along the lower trunk of young trees.
temperature for survival:
trees will grow in some of the hottest regions of the world as long as water is available for growth. More species of trees are in the forests at the equator than in forests in other regions. Some trees live in parts of the world where temperatures far below freezing. Wood will freeze, but the water is in the spaces between the living cells, and this prevents the living cells from bursting.
forms on the upper side of the lean in woody angiosperms, as evidenced by widely spaced rings.
located at the end of the shoot.
a device or configuration that secures the end of a cable to the anchor in a cabling or guying installation.
used to form a cabling termination and includes dead-end grips, thimbles used in eye-splice configurations, cable-end terminations, and swag-stop terminations.
an oblong galvanized or stainless steel fitting with flared margins and an open-ended base.
selective pruning to reduce density of live branches.
a machine-thread, steel rod used for through-brace installations.
a brace formed by installing hardware completely through a branch, leader, or trunk.
anchors, cables, braces, eye bolts, and threaded-steel rods that pass completely through the branch, leader, or trunk, secured with nuts and heavy-duty washers or cable-end termination.
a small, lightweight line with a weighted end used to position a climber's rope in a tree.
the measurement, sawing, preparing and transportation of timber
a group of cells, all of the same kind, and closely connected to perform a special function.
an invention of modern science to extract cells of desirable trees and grow these cells into trees within laboratory conditions. Trees from this process are genetically identical to the parent.
the reduction of a tree's size using heading cuts that shorten branches back to a predetermined crown limit. Topping is not an acceptable pruning practice.
the poisonous secretion of a tree.
conifers have tracheids which are dead, enlarged parenchyma, single-celled transport "pipes" for liquids in xylem.
the removal of loose, damaged tissue from in and around a wound.
the process in which trees absorb water through their roots and transfer it up to the leaves where it participates in photosynthesis before it evaporates into the environment through leaf pores.
the movement of liquids and materials in solution from one place to another. There are two basictransport types: passive and dynamic; and two basic directions; radial and axial or longitudinal. Axial transport is mostly downward in phloem, and mostly upward in xylem or wood. Radial transport is mostly out-ward early in the growing season and mostly inward later. In newly forming tissues that have not yet become woody, transport may go in either direction in the xylem and phloem. The photosynthate sugars are formed in the leaves and move to a place where they are used for energy or being convened to energy reserves. Water and essential elements from the soil move upward in the tracheids.
any woody plant that may grow more than 20 ft (7 m) tall and usually has one main stem.
the economic, environmental, and social benefits that a tree provides to a community.
the science of all factors, about trees.
a process that starts after wounding and involves many microorganisms and pathogens as highly ordered wood becomes disordered.
a tree manufactures its own food, with water, essential elements (such as phosphates, iron, and magnesium) and the energy trapped from the sun.
a comprehensive list of individual trees containing descriptive and desired information for all or a portion of the project area.
tree lawn or parkway:
a strip of green between a city street and the sidewalk. Has many local names such as alley, boulevard, city right-of-way, devil strip, flower border or tree border, garden strip, green space or green surface, hell strip, landscape strip, nature strip, neutral ground, parking strip, pedestrian buffer, planting strip, sidewalk landscape, swale, terrace, utility strip, verge or grass verge, or road verge.
the policies used by communities to attain a healthy, vigorous, and managed urban forest along with the authorization and standards to manage the community trees.
the study of how trees grow and develop in terms of genetics, biochemistry, cells, tissues, and organ functions.
tree protection zone:
a designated area around trees where maximum protection and preservation efforts are implemented usually to minimize soil compaction.
the likelihood and consequences of failure of a tree or tree parts.
tree risk assessment:
establishing the criteria and priorities for inspecting, analyzing the risk present in trees, and identifying trees that meet the risk criteria.
tree risk management plan:
involves the assessment of trees, criteria and priorities for analyzing risk, and mitigation options.
the two basic types of tree roots: woody and non-woody. Woody roots are organs that mechanically support the tree, store energy reserves, and transport liquids. Non-woody roots are organs that absorb water and elements essential for growth. Further, there are two types of structures that form on non-woody roots: root hairs and mycorrhizae. Root hairs are most common on young trees and trees growing in containers. Root hairs are not common on mature trees, especially forest trees. Roots may develop special roots such as prop roots, deep roots, shallow roots, pioneer roots, mycorrhizae, nodules, hairs, and tap roots.
an evaluation of a tree's quality, volume, species, and other factors in order to determine the highest and best uses of its products.
trees compete for space in soil for water and nutrients, and in the space above ground for energy from the sun. In the warm rain forests, water and temperature are not limiting factors. As space becomes more restrictive, the shape of trees is affected because branches that grow in a horizontal position will not live long. Trees that reach the top of the forest canopy rapidly then produce co-dominant stems, to grow over other trees.
the connection and use genetic information in ways that ensure continuous high-quality survival against all the connected members of the forest system.
triangular cabling system:
consists of connecting tree parts in combinations of threes. This method should be preferred when maximum cabling support is required.
fine hairs that cover tree leaves.
the additional length over and above the specified log length on the end of a log to allow space for likely cracks and deterioration.
tree movement toward or away from a stimuli.
the main stem and bole of a tree, beginning at the flare and ending at the highest main scaffold branch. Some trees have multiple trucks called multiple leaders.
the process of injecting a liquid containing a fertilizer or pesticide into the tree.
used on young trees to prevent the green cortex from photosynthesizing. There are no data to show that trunk wraps prevent "frost" cracks or "sun" scald.
a drop-forged, closed-eye device for adjusting tension on a cabling system.
small branches on a tree having a terminus.
the fork or crotch of a branch and trunk or another branch.
urban and community trees:
urban forests and natural systems in and around populated areas such as cities, suburbs, towns, and villages.
all the trees within a community and can include trees along the streets, in parks and public open spaces, in forests, and on private property.
urban forest by-products:
material from trees that includes the leaf, twig, branch, trunk, and/or root.
urban forest management plan:
a plan to evaluate the tree resources in a community, develop goals for health and viability of the urban forest, prescribe strategies for tree management, and monitor progress.
urban forest products:
products made from material produced in the pruning and/or removal of trees including, but not limited to, whole trees, logs, branches, bark, leaves, chips, and stumps.
populated locations normally associated with human activity.
an entity or individual processing, manufacturing, distributing, or consuming products from urban trees including compost, lumber, and wood chips.
an entity that delivers a public service such as electricity or communications.
any private, public, or cooperatively owned system for transmitting, or distributing electricity, heat, gas, oil, crude products, communications, water, steam, waste, or storm water and transportation, which directly or indirectly serve the public.
a corridor of land over or through which utility facilities are located. The utility may own the land in fee, an easement, or have certain franchise or license rights to construct and maintain utility facilities. The utility may selectively prune trees to prevent the loss of service and damage to its equipment.
vascular meristem or cambial zone:
increase the girth or circumference of the tree.
vegetation that is desirable and/or suitable to the intended use of the site.
vegetation that is undesirable, presents a safety hazard, or is unsuitable to the intended use of the site.
an individual engaged in the profession of vegetation management who, through appropriate education and related training, possesses professional competence.
an uncommon form of vegetative propagation occurs when stems come in contact with the soil and the cambium tissue forms roots. Trees from this process are genetically identical to the parent.
made from a type of xylem cell. Vessels are vertically aligned tubes that transport water and mineral nutrients. Other vessel conduits connect from the sides to form a transport pathway from root tips to leaf tips. Conifers have tracheids. Woody angiosperms have vessels.
old trees are also called memorial trees, historic trees, and over-mature trees. Most veteran trees have been injured from storms or human activities. Despite the problems, they continue to grow new parts and provide habitat for local wildlife.
the capacity to resist strain. It is a genetic factor and a potential force against any threats to survive. Trees that compartmentalize effectively are more vigorous than those that compartmentalize poorly.
cause problems for trees as they twist about young stems and kill them. They can make conditions perfect for fungus fruit bodies. Vines may grow over tree crowns and shade the leaves. Their weight could cause branches to break. Vines at the base of trees make suitable places for small animals to live. Some vines will girdle small trunks and branches. Fast growing vines may also compete with tree roots for water.
the amount of pathogen propagules required to cause a disease to develop. If a few bits of a pathogen cause disease symptoms it is very virulent. If it takes a great amount of the pathogen to cause similar symptoms, the pathogen is weakly virulent.
selective pruning to allow for a specific view to be preserved or enhanced.
visual tree assessment:
a method of evaluating structural defects and stability in trees.
the ability to grow under ambient conditions.
CODIT Wall 1.
After being wounded, the tree responds by plugging the vertical vascular system above and below the wound.
The last cells to form in each growth ring make up the tangential walls that are generally continuous around each growth ring. Wall 3. This is the strongest wall in the tree at the time of wounding.
This wall separates the tissue present at the time of wounding from tissue that forms after. It becomes the strongest of the four walls.
water-insoluble nitrogen (WIN):
the amount of fertilizer nitrogen not readily soluble in cold water.
water in wood:
cell walls of wood in sapwood are saturated with water.
occurs where water has replaced oxygen and iron and manganese become the electron acceptors. This leads to the precipitation of iron and manganese so the tree does not get any of these elements.
all the land surrounding a stream or a river that drains into that stream or river.
new stems originating from epicormic buds or shoots.
a plant that has no use or beauty and is hindering the growth of a superior plant.
a term used for both a disease and for wood altered as a result of a disease. Wet-wood is mostly infected by anaerobic bacteria which disrupts membranes, pH, and free oxygen as micro spaces are filled with water.
a young tree without branches.
a tree or branch that is so weak that it could fall, causing injury to a person under the tree or branch.
wire rope clamps:
a clamp consisting of a "U" bolt, bracing plate, and fastening nuts.
are bundles of twigs or small branches caused by mites, viruses, or other organisms that stimulate broom formations.
made of cellulose, lignin, and hemicelluloses which create thick, tough boundaries or walls. These cells are transport cells or vessels, tracheids or mechanical support cells, fibers, fiber tracheids, cells that contain living substances, parenchyma, axial, and radial. All wood cells are born alive. Wood cells are arranged in ways that support the tree as a biological and mechanical system.
a material placed on the soil surface composed of ground wood, bark, and leaves usually generated by sending tree parts through a wood chipping machine.
in most trees about 90% of the growth increment will be formed in about 6 to 8 weeks after leaf formation and as the soft xylem begins to become lignified.
tree parts that have wood-like consistency.
roots mechanically support a tree, store energy reserves, and transport liquids that contain lignin along with cellulose and hemicelluloses in their cell walls. Woody roots have an outer bark and contains suberin. Woody roots usually grow outward and downward.
have more lignin than woody roots. Woody stems have a pith and store less starch than woody roots. The vessel arrangement in woody stems is less diffused than in the woody roots.
an opening caused when the bark of a live branch is cut, by mechanical damage, or other natural forces. If the wound occurs during the growing season, wait until after the growing season has ended to removing the loose bark. Do not to increase wound size or penetrate the wood.
a very tough, woody tissue that grows behind a callus and replaces it in that position. When wound-wood closes wounds, then normal wood continues to form.
a carotenoid alccohol that become the orange pigments in leaves.
a transport tissue in vascular trees. It transports free water and substances dissolved in it, from absorbing non-woody roots to leaves. When xylem is lignified it is then called wood. This makes the cell walls very tough and is a unique feature of trees.
young tree training:
deals with the pruning of young trees to correct or eliminate weak, interfering, or objectionable branches and to improve the tree's structure.
THIS SET IS OFTEN IN FOLDERS WITH...
ISA Arborist Chapter 2
Arborist Certification Test Prep
Certified Arborist Exam SECRETS Study Guide
ISA Arborist Chapter 8: Pruning
YOU MIGHT ALSO LIKE...
Science Practice SOL
Ornamental Horticulture Test 1
Aeps 120 Lab final
1.0 Biology; Biology and Scientific Meth…
OTHER SETS BY THIS CREATOR
Plant list 2
Plant list 1
Municipal Chapter 2 Terms
Module 1 Introduction to TRA