ISA- Arborist Exam Review Graded A+

abiotic - ANSWER pertaining to the nonliving parts of an ecosystem, such as soil particles, bedrock, air, water. abscisic acid (ABA) - ANSWER a plant hormone that stimulates stomatal closure and promotes seed and bud dormancy. abscission zone - ANSWER a wall of cells at the base of a petiole, that allows the leaf to separate from the stem. - two functions: leaf drop and to protect the region of the stem against desiccation acceptable risk - ANSWER the amount of risk that an owner is willing to accept before tree failure. acidic soil - ANSWER having a pH less than 7.0, in contrast with alkaline which has a pH that is higher than 7.0. actinomycetes - ANSWER 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. action threshold - ANSWER the point at which a pest requires the implementation of a management tactic or control. acute crotches - ANSWER 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. adaptive growth - ANSWER 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. adsorption - ANSWER adhesion on contact of molecules to the surface of solids or liquids with which they are in contact. adventitious/epicormic growth - ANSWER 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. adventitious root: - ANSWER 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. aerial roots: - ANSWER roots that grow from stems toward the soil with the capacity to become prop roots when they anchor in the soil. aerobic microorganisms - ANSWER these microbes require free, gaseous oxygen for growth. aggregate: - ANSWER 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: - ANSWER is a land use management system in which trees or shrubs are grown around or among crops or pastureland. ait terrminal - ANSWER the uppermost point of a lightning protection system in a tree. It is usually made of copper. alkaline soil - ANSWER having a pH greater than 7.0, in contrast with acidic soil which has a pH lower than 7.0. alkaloids - ANSWER substances that are produced by trees and contain nitrogen and are used by humans for medicines. allelopathy - ANSWER 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. amy;lase - ANSWER an enzyme that can change the starch chains back to glucose molecules. anerobic microorganism - ANSWER these microbes live in the absence of free oxygen. anon-eye nut - ANSWER drop-forged eye nut is used to fasten through-hardware anchor(s), used when cabling trees. Advantage is the length of the rod can be adjusted. angiosperms - ANSWER hardwood trees that have covered seeds such as oaks and maples. The seed is born within an ovary. anions - ANSWER negatively charged atoms or molecules in fertilizer that become available to the plant in water. anther - ANSWER the pollen producing part of a flower. anthocyanin - ANSWER a chemical that gives the red pigments to leaves and other plant organs. apical meristem - ANSWER meristems that increase the length of stems and roots, and produce flowers. apoplast (apoplasm) - ANSWER the framework of non-living cells and cell walls in wood and bark. The apoplast stores bound water, which does not flow. arboriculture - ANSWER 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. arborist - ANSWER 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. arbuscular mycorrhizae: - ANSWER commonly called endomycorrhizae infects the internal tree root cells and are most common in deciduous forests. armillaria root disease: - ANSWER cause death to trees under all types of stress by reducing absorption and translocation of water and minerals from the soil to the tree. arthropods: - ANSWER microscopic insects and mites that are vital in processing soil organic matter and mineralizing detritus. ascender: - ANSWER 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. axial parenchyma - ANSWER cells that run in a vertical direction on the trunk. axil - ANSWER the point of attachment of a leaf petiole to a stem. back cut - ANSWER a cut made on a tree trunk or branch, opposite from the notch, face cut, or undercut. bacteria - ANSWER 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. barrier zone - ANSWER a barrier zone is a chemical boundary within the wood present at the time of wounding which resist the spread of pathogens. balancer - ANSWER a rigging sling(s), usually with at least one spliced eye and a Prusik to position the load line. bark - ANSWER 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. bark distortions - ANSWER overgrown knots, mechanical wounds, holes of all types, ingrown bark, and other defects which can be seen on the bark appearance. bark fissures - ANSWER 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. barrier zone - ANSWER chemical boundary within wood that is present at the time of wounding and resists the spread of pathogens. basal rot or butt rot - ANSWER decay of the lower trunk, flare, or buttress roots, also called butt rot. basic assessment - ANSWER a detailed visual inspection of a tree and the surrounding site. bast fibers - ANSWER elongated, tapering, thick-walled cells that provide strength to wood. berry - ANSWER a simple fleshy fruit bifurcation - ANSWER the natural division of a branch or stem into two or more stems. bimetallic connector: - ANSWER 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. biological control management: - ANSWER the management of pests using organisms that focus on control of plant competition, allelopathy, animals, insects, or pathogens. biomass - ANSWER a mass that contains some form of living cells. biorational pesticide - ANSWER a pesticide formulated from naturally occurring plant extracts, microbes, or microbial byproducts. biostimulant - ANSWER 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. biotic - ANSWER pertaining to living organisms and their ecological and physiological relations. bleeding - ANSWER the flow of sap from plant wounds. blight - ANSWER any disease that kills young plant tissues. block and tackle - ANSWER a system of two or more pulleys and rope used to lift or pull heavy loads. with rotating sheaves with bearing and bushing to reduce friction bole - ANSWER the main trunk of a tree below the branches. bore cut - ANSWER using the tip of a chain saw to cut into or through the middle of a piece of wood. botanicals: - ANSWER compounds and pesticides made from plants. bracing - ANSWER 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. bract - ANSWER a modified leaf that compliments the flower. branch collar - ANSWER the swollen area of bark at the underside of a branch. branch bark ridge - ANSWER 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 - ANSWER 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. bridge graft - ANSWER 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. bollards - ANSWER friction device-posts strapped to a tree for taking wraps with a load line buds - ANSWER organs that contain preformed parts of leaves or needles, flowers, or both. Buds are structures that are made up of embryonic shoots. balance the limb (with a second rope) - ANSWER branch removal involving a second rope to reduce swing and dynamic loading butt tied vs tip tied - ANSWER rigging line is tied to the butt end of the branch vs rigging lined tied to the tip end . buffering capacity - ANSWER the ability of a soil to maintain its pH. bulk density - ANSWER the mass of soil per unit volume used as a measure of compaction.