Arboriculture Glossary of Terms

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  • t

  • Tabernaemontana divaricata
  • rope used to control the swing of a limb being removed or to control the direction or fall of a tree or limb being removed.
  • organic substances produced by trees. Believed to be involved in a tree's chemical defense processes.
  • central. vertical root growing directly below the main stem or trunk that may or may not persist into plant maturity.
  • type of perennial canker that gains its name from the appearance caused by concentric rings. each of which represents a year's growth of wound tissue around the infected area.
  • an organism that is intended to be damaged or killed through the application of a pesticide. Timing. formulation. and application technique may be manipulated to reduce impact on nontarget organisms (see nontarget organism).
  • process of branch removal to achieve a specified goal in which the pruning cuts are made at nodes and in relation to the positions of the branch collar and branch bark ridge.
  • tightened to the point of eliminating visible slack.
  • type of friction hitch used by climbers for fall protection during ascent. descent. and work positioning.
  • see slack tender.
  • any of several hierarchic levels in the classification of living organisms.
  • science that studies the description. denomination. and classification of living organisms f based on their similarities and differences (contrast with anatomy. morphology. and physiology).
  • Tree Care Industry Association (formerly NAA)
  • Town and Country Planning Act
  • trunk diameter
  • Tree and Design Action Group
  • trunk diameter ratio
  • tie. dress. and set
  • Tecomaria capensis 
  • in structural pruning of young trees. branches (generally the lower branches) that are left in place or subordinated but will be removed later in forming the permanent scaffold framework of a tree (contrast with permanent branches).
  • force at which a new piece of equipment or rope in testing fails in tension under a static load.
  • instrument used to measure soil moisture.
  • stretching or pulling force on any material or substance.
  • bud at the tip of a twig or shoot. Apical bud (contrast with lateral bud).
  • Indian Almond
  • a device or configuration that secures the end of a cable to the anchor in a cabling or guying installation.
  • hardware used to form a termination. Termination hardware includes but is not limited to dead-end grips. thimbles used in eye splices. swage sleeves. and cable-stop termination devices .
  • These are often called primary reproductives. At certain times of the year, a mature colony will produce these in large numbers and they will swarm when conditions are right. This generally coincides with rainfall. Formosan termites tend to swarm at dusk or early evening. These are often called “swarmers” and can be seen around street lamps and other lit areas. Their flights are generally short. Although not strong flyers, they can be carried by wind and air currents. Formosan termite(...)
  • The king or male termite is an extremely important member in the life of the colony. The king assists in the excavation of the nuptial chamber, and shares in the early brood rearing. It mates with the queen throughout his life. The termite king starts life as a flying termite. After a brief flight, he will lose his wings and be confined to the ground.
  • Larvae are the immature stages and resemble very small workers. Larvae grow through a number of molts to become workers, nymphs or soldiers. They are cared for by workers until they have reached the worker stage. Nymphs are immature individuals with wing buds. Then through a number of molts, they eventually become alates (flying termites). Nymphs are also cared for by workers until they have molted into alates and fly out.
  • The primary role of the queen is reproduction. Once mated with the king, the queen begins her life-long role as egg producer. The queen can live for ten or more years and can produce over 1,000 eggs per day. Her stomach expands as her egg-laying capacity increases. She normally lives within a chamber where she is cared for along with the king. The termite queen begins her life the same as the king as a flying termite.
  • The main function of the soldier termite is to defend the colony. Soldiers have an enlarged, hard head with two large jaws. When openings occur in the galleries, they quickly position themselves at the opening with their jaws open and pointing outwards from the hole. When alarmed, soldiers termites will bang their heads against the gallery walls to alert the rest of the colony. In addition to having large jaws, the Formosan termite soldier has a large opening in the head above the jaws(...)
  • The termite worker caste is by far the largest group within the colony. These creamy white, soft-bodied insects are the ones that damage wood and other cellulose containing materials as this is their primary food. Workers are blind and wingless. They are responsible for nearly all the work within the colony. These activities include caring for the eggs and the young, constructing tunnels, excavating galleries, building and repairing the nest system when damaged, obtaining food and feeding(...)
  • method used to lower the soil grade in steps or stages .
  • trunk formula method
  • tree growth regulator
  • Yellow Oleander
  • 1) an oblong. galvanized or stainless-steel fitting with flared margins and an open-ended base. 2) a device used to increase the bend radius of and reduce wear on a rope when attached to hardware.
  • in pruning. the selective removal of live branches to provide light or air penetration through the tree or to lighten the weight of the remaining branches.
  • sharp. hard. and woody part of certain plants that is generally a modified leaf.
  • a machine-threaded steel rod used for through-brace installations.
  • climbing technique in which the climber maintains three points of contact with the tree.
  • 1) in Integrated Pest Management. pest population level requiring action. 2) in risk assessment and management. level of risk requiring action.
  • (1) in Integrated Pest Management. pest population levels requiring action. (2) in hazard assessment. risk assessment and risk management. levels or risk requiring action.
  • cable anchors or bracing rods that pass completely through an oversized. pre-drilled hole in a trunk or branch and are secured with nuts and washers (contrast with dead-end hardware).
  • in utility line-clearance pruning. directional pruning that removes branches from the center of the tree crown to provide clearance from utility lines. leaving selected overhanging branches above.
  • weighted sack used to set climbing or rigging lines in trees. Usually a shot-filled. teardrop shaped bag.
  • weighted ball used to set climbing or rigging lines in trees. Usually a rubber-coated. weighted sack or pear-shaped ball. ...
  • knot tied in a rope to form a weight for throwing to set climbing or rigging lines in trees.
  • thin. lightweight cord attached to a throwbag or throwing ball used to set climbing or rigging lines in trees.
  • Chinese Arborvitae - Oriental Arbor-vitae
  • Thunbergia erecta
  • to set a climbing line in a tree and secure it with an appropriate hitch or device.
  • position in a tree (in a natural or false crotch) through which the climbing line is set to serve as the pivot point for work positioning.
  • knot consisting of a series of wraps on a line and used to secure the line to a limb or tree.
  • tying a line on the tip (brush) end of a branch to be removed. allowing the branch to be lowered butt-end first.
  • similar to topping except heading cuts are made through smaller (pencil-sized) branches in the outer periphery of the crown.
  • group of cells with similar structure that have a special function.
  • image. produced by processing signals (including-but not limited to-sound waves. x-rays. and magnetic fields). and transmitted through an object. that depicts the relative density of that object.
  • s

  • Sonic Tomography tracks the speed of sound waves through the trunk or large branch of a tree. The tomogram is an image of the scanned area, which is more or less a flat plane cross-section through the tree or branch.
  • t

  • in carabiners. a type of gate latch mechanism. Also called notch gate or pin lock. Has the disadvantage that it may catch on a rope (contrast with key lock).
  • the second of three pruning cuts used to execute a removal cut. Made from the top of the branch downward. directly above the undercut when using a chain saw. or slightly farther out when using a hand saw.
  • chain saw with the center of gravity just above the engine. where the right (trigger) handle is located.
  • specialty pruning technique in which a f perennial (and usually evergreen) shrub or tree is trained into a distinct shape. by means of regular pruning and/or hedging.
  • inappropriate pruning technique to reduce tree size. Cutting back a tree to a predetermined crown limit. often at internodes.
  • hinge cut used when removing the top from a tree in the tree removal process.
  • surface layer of soil that may be rich in nutrients from decaying plants and bacterial material. often removed when sites are graded in preparation for construction or development.
  • wrongful acts. other than breach of contract. for which civil action may be taken.
  • tree preservation order; tree preservation ordinance
  • tree protection plan
  • tree protection zone
  • tree protection zone barrier
  • tree risk assessment
  • The Guidelines for Tree Risk Assessment and Management (TRAM) Arrangement serve to provide technical and performance guidance on tree risk assessment, management, monitoring and maintenance. The key objectives are to: (a) Maximise public safety (b) Establish sustainable tree care practices The Guidelines for TRAM Arrangement are based on international best practices with due consideration to the circumstances in Hong Kong. They should only be applied, supervised and endorsed by qualified(...)
  • see load-transfer line.
  • an electrical device for changing the voltage of alternating current.
  • movement of sugars in the phloem.
  • in an electric utility system. wires used to transmit electricity from generating stations to the distribution network or between distribution substations. often carrying in excess of 69.000 volts (contrast with distribution lines).
  • water vapor loss through the stomata of leaves.
  • plant stress following transplant; characterized by reduced growth. wilting. dropping foliage. or death.
  • process of moving a plant to a new location.
  • ISA Tree Risk Assessment Qualification
  • Identify valuable trees (i.e. Old and Valuable Trees and stonewall trees) and high risk trees within high priority areas. Assess tree conditions in accordance with a standardised format with emphasis on the risk angle.
  • group of citizens. both laypeople and professionals. that are appointed to support and sometimes oversee urban forestry programs; may also include elected officials.
  • uprooting or mechanical breakage of a tree. its parts. and/or surrounding soil.
  • Tree Research and Education Endowment Fund
  • see dead-end grips.
  • (Form 1) the purpose is to facilitate an initial screening of trees. Each tree in a tree group has to be inspected systematically for identifying potential tree hazards or tree required for detailed individual tree risk assessment (Form 2).
  • chemical that slows terminal growth by reducing cell elongation.
  • managing trees and their surrounding environment to promote tree vigor. structural stability. and natural defense mechanisms.
  • record of trees within a designated area that provides specified identification and condition information to be used for management decisions and actions.
  • enclosed planting bed surrounding a tree. often within a paved area or adjacent to a street.
  • in the United Kingdom and other countries. an individual responsible for the care and protection of public trees and greenspaces (see city forester. urban forester. tree warden. and municipal arborist).
  • tree-specific law that defines a public agency's authority. describes required conditions or actions. establishes penalties for nonconformance. and identifies who is responsible for enforcement and oversight. In Canada. tree by-law.
  • damage that occurs where enlarging roots and trunks displace and/or crack sidewalks. curbs. streets and other paved areas.
  • in the United Kingdom (and being adopted elsewhere). a legal regulation. established by a local authority. that protects a tree or multiple trees.
  • (TPZ) defined area within which certain activities are prohibited or restricted to prevent or minimize potential injury to designated trees. especially during construction or development.
  • (TPZB) various devices. including fencing. berms. or signs. installed to limit access to tree protection zones (or similarly designated areas) during construction. development. or site disturbance.
  • various devices. including fencing. berms. or signs. installed to limit access to tree protection zones (or similarly designated areas) during construction. development. or site disturbance.
  • defined area within which certain activities are prohibited or restricted to prevent or minimize potential injury to designated trees. especially during construction or development.