Glossary of Terms

The following glossary of terms has been created to provide clear definitions for unfamiliar or specialized terms that you may see in your quote or hear in conversations with the Logan Tree Experts team. 

Abiotic disorder– plant problems caused by nonliving agents

Absorbing roots– fine fibrous roots that take up water and nutrients, mostly located in the top 12” of soil.

Acute– disorder or disease that occurs suddenly or over a short period of time

Aeration– provision of air to the soil to alleviate compaction and improve soil structure

ANSI A300 standards– industry-developed standards of practice for tree care

Air spade– a pneumatic air gun used to excavate and alleviate compaction 

Apical– having to do with the tip

Apical bud– terminal bud on a stem

Apical dominance– a condition in which the terminal bud inhibits the growth and development of lateral buds

Arboriculture– the science and art of caring for trees, shrubs, and other woody plants in landscape settings.

Arborist- a person possessing the technical competence through experience and related training to provide for or supervise the management of trees or other woody plants in a landscape setting.

Balled and Burlapped (B&B)- having the root system and soil wrapped in burlap for the movement and planting of a tee or plant

Bare root– tree or other plant planted with exposed roots

Bark tracing– cutting or removal of damaged bark to help remediate wound

Biological control– method of controlling plant pests through the use of natural predators, parasites or pathogens

Biomass- the total mass, at a given time, of living organisms of one or more species per unit area (species biomass) or of all the species in the community (community biomass).

Biotic disorders– disorders caused by a living agent

Bifurcation– the division of something into two branches or parts. 

Blight– any disease, regardless of the causal agent that kills young plant-growing tissues

Bracing– installation of steel rods or bolts through the stems or limbs, to reduce the potential of structural failure

Branch union– point where a branch originates from the trunk or another branch

Bud– small lateral or terminal protuberance on the stem that may become a flower, shoot or leaf

Buttress roots– roots at the base of the trunk, trunk flare

CSA– Canadian Standards Association 

Cabling– installation of cables to provide additional support or to limit movement and stress of limbs.

Canker– localized diseased area, often shrunken and discolored, on stems and branches

Cavity– an open and exposed area of wood, where the bark is missing and internal wood has been decayed and dissolved.

Central leader– the main stem of a tree

Chronic– disorder or disease occurring over a large period of time

Clearance Pruning– Pruning of specific branches or limbs to create space from a specific object, i.e., roof, driveway.

CODIT– Compartmentalization of damage in trees. How trees create barriers to resist damage and decay.

Collateral damage- damage inflicted on something other than an intended target

Compaction– the compression of soil, causing a reduction of pore space and an increase in the density of the soil. Tree root growth and health are adversely affected in compacted soil.

Consultation- A formal meeting with an expert or professional to discuss or seek advice. Utilizing an expert’s knowledge to be more informed.

Conifer– a plant that bears seeds in a cone. i.e. Evergreen

Conk– the fruiting body of a fungus

Contact insecticide– materials that cause injury or death to an insect after coming in contact with the pest

Container grown– tree or shrub grown that has been grown in a container

Controlled release fertilizer– slow release or slowly soluble form of fertilizer

Cracks– defects on trees that, if severe, may pose a risk of failure

Critical root zone– a portion of the root system that is the minimum necessary to maintain the vitality or stability of the tree. Encroachment or damage to the critical root zone will put the tree at risk of biological death and/or structural failure.

Crown cleaning– pruning method of removal of water sprouts and dead, dying, diseased, crossing, and hazardous branches from a tree

Crown reduction– pruning method of reducing the height or spread of a tree

Crown restoration-pruning method of restoring the canopy of a tree that has been damaged by biotic of abiotic means

Decay– progressive deterioration of organic tissues, usually caused by fungal or bacterial organisms, resulting in loss of cell structure, strength, and function. In wood, a loss of structural strength.

Down only– a description of a project that requires no cleanup or movement of material other than to ensure a safe worksite.

Deciduous– perennial plant that loses all its leaves at one time during the year.

Defoliation– loss of leaves.

Dormant- a seasonal quiescent state in which the plant suspends growth. Usually occurs during winter months.

Dual-stemmed– a tree or plant with two dominant stems or leaders

Electrical conductors– overhead or underground electrical devices including hydro, communication, etc

Estimate– an approximate calculation or judgment of the value of a product or service.

Evergreen– a plant that retains its leaves for more than one growing season.

Fertilization- the process of adding nutrients to a tree or plant; usually done by incorporating the nutrients into the soil, but sometimes by foliar application or injection directly into living tissues.

Firewood length– denotes wood cut into approximately 16” unless previously discussed and agreed upon.

Foliage- the live leaves or needles of the tree; the plant part primarily responsible for photosynthesis.

Foliar application– application of fertilizer or other substances directly to leaves

Fruiting bodies– the reproductive structures of fungi

Full cleanup– a description of a project that requires cleanup of all tree material above ground except the trunk unless agreed upon

Fungicides– chemical compounds that are toxic to fungi

Fungus– any of a group of spore-producing organisms feeding on organic matter, including molds, yeast, mushrooms, and toadstools.

Girdling roots– root(s) that grow around a portion of a trunk or other roots causing inhibition of water and nutrients by choking the flow of vascular elements.

Growth Increment– the incremental growth added as new wood each growing season over existing wood. This is seen as growth rings in cross-sections of wood.

Hardwood– trees that lose their leaves in autumn; also refers to the wood produced by these trees. Hardwoods are the predominant type of tree in the deciduous forest.

Hazard assessment– a process in which the risk potential of a tree is assessed

Hedge– a fence or boundary formed by closely growing bushes or shrubs

Hedging– the maintenance or shaping of a hedge

Herbicide– a chemical that kills plants or inhibits their growth; intended for weed control.

Horticulture– the cultivation of fruits, vegetables, and ornamental plants.

Hydro disconnect– the de-energization or disconnecting of electrical power to safely perform tree work in proximity to energized conductors

Included bark– bark that becomes embedded in a union due to tight attachment angle creating a weakened attachment

Inorganic fertilizer– mineral fertilizer, not originating from plant or animal

Insecticide– a chemical that kills insects.

Insecticidal soap– mild salts of fatty acids that disrupt pest life processes

Integrated Pest Management (IPM)- a system of controlling pests and their damaging effects through mechanical, chemical, biological, cultural, and regulatory techniques.

ISA- the international society of arboriculture

Landscape– areas of land that are distinguished by differences in landforms, vegetation, land use, and aesthetic characteristics. A maintained portion of land.

Leader-the primary terminal shoot or trunk

Liability– something for which one is responsible, legal responsibility

Lion tailing– poor pruning practice of removing internal growth and only leaving foliage at the end of the limb

Macronutrient– any of the essential elements required by plants in relatively large quantities

Manageable size/ length– description of size in which wood may be left on site. Wood will be liftable and in multiples of 16” 

Micronutrient– any of the essential elements required by plants in relatively small quantities

Mitigation– action taken to alleviate potential adverse effects. Also commonly used to mean compensation for damage done.

Mulch– any material such as wood chips, straw, sawdust, leaves, and stone that is spread on the surface of the soil to protect the soil and plant roots from the effects of raindrops, soil crusting, freezing, compaction, and evaporation.

Multi-stemmed– a tree or plant with more than two stems of leaders

Mycorrhizae-a symbiotic association between a fungus and the roots of a plant

Natural pruning– the natural death of branches on the stem of a tree from such causes as decay, or deficiency of light or water, or snow, ice, and wind breakage.

Natural target pruning– pruning technique in which only branch tissue is removed, with the cut placed just beyond the branch collar.

Nematode– microscopic roundworm that can feed on plant tissues and may cause disease

Nutrients– the substances, such as mineral elements and compounds, including water and air, that a plant synthesizes into the complex compounds of tissue.

Organic fertilizer– fertilizer derived from plants or animals

Organic layer– layer of organic matter at the soil surface

Overmature– tree or stand that has passed the age of maturity where the rate of growth has diminished and the trees are weakened.

pH– a measure of acidity or alkalinity of a medium

Plant Health Care (PHC)- a holistic and comprehensive program to manage the health, structure, and appearance of plants in the landscape

Planting specifications– detailed plans and statements of particular procedures or standards for planting

Pruning– selective removal of woody plant parts of any size, using saws, pruners, clippers, or other pruning tools.

Radial aeration– means of aerating the soil in the root zone by removing and replacing soil in a spoke-like pattern, aka radial trenching

Raising– pruning method to remove lower limbs to provide clearance

Reduction– pruning method to reduce the length of a limb or leader

Removal– the process or act of taking down a tree or shrub. Removal does include stump and root removal unless specifically agreed upon

Resistograph®- a gear-driven drilling instrument which inserts a three-millimeter-diameter probe into a tree, and graphically or digitally records resistance to the probe; used to detect decay and defects.

Retrenchment– the natural process of a tree reducing in size to minimize structural and biological stress. Retrenchment pruning mimics this process. See reduction

Risk assessment- a process of determining the level of risk posed by a tree

Risk management– a process of controlling risk in tree management

Root System– the portion of the tree containing the root organs, including buttress roots, transport roots, and fine absorbing roots; all underground parts of the tree.

Root Zone– the area and volume of soil around the tree in which roots are normally found. May extend to three or more times the branch spread of the tree, usually staying within the top 18” of the soil but can extend deeper.

Scaffold branch pruning– pruning method to establish proper branch spacing

Senescence– the process of aging, decline, and death.

Secondary leader– a subordinate stem or limb

Site line pruning– selective pruning to create a view, vista

Skeletonized– leaves that have had the tissue removed between the veins by insects

Slow-release fertilizer– fertilizer that is at least 50% water-insoluble nitrogen

Softwood– cone-bearing trees with needles or scale-like leaves; also refers to the wood produced by these trees. Softwoods are the predominant tree type in coniferous forests.

Soil– a dynamic natural body composed of mineral and organic materials and living forms in which plants grow.

Soil amendment– material added to soil to improve its physical or chemical properties

Soil analysis– analysis of soil to determine pH, mineral composition, structure, etc

Soil profile– vertical section through a soil, through all horizons

Species– the main category of taxonomic classification into which living organisms are subdivided, comprising a group of similar individuals having several correlated characteristics.

Staking– supporting a newly planted tree with stakes

Stress– In arboriculture, the adverse alteration of tree health by abiotic or biotic factors.

Structural defects– flaws, decay, or other faults in all parts of the tree that may lead to failure

Structural pruning– Pruning to improve the architecture of the tree by selecting dominant leaders, creating proper limb spacing (scaffolding), and removing poor branch attachments.

Stump cut low– leaving the stump approximately between 3-8” above grade after a tree removal unless previously agreed upon

Subordination– pruning method to reduce or remove the leader and allow a secondary leader to remain

Sucker– shoot arising from the roots

TRAQ (tree risk assessor qualification)-  ISA qualification and approved process to assess and record tree risk assessments

Target– any person or object within reach of a falling tree or part of a tree, that may be injured or damaged.

Thinning– pruning method in which branches are removed at their point of origin.

Topping– improper and non-specific reduction in tree height

Tree protection zone– a designated area around trees where maximum protection and preservation efforts are implemented to minimize soil compaction, mechanical damage, etc.

Trunk Flare– the enlarged area at the base of the tree indicating the transition of the trunk into the roots

Urban forestry– management of naturally occurring and planted trees in urban areas

Underground targets– any infrastructure beneath grade that could be affected by a tree work project, i.e septic, irrigation, etc.

Vertical mulching– the filling of vertical holes with materials to add organic material, increase water and air infiltration, or reduce compaction 

Vigor– overall health; the capacity to grow and resist physiological stress.

Vista pruning– selective pruning to create a view, sightline

Visual Tree Assessment- Method of evaluating structural defects, health, vigor, and stability in trees.

Water sprout– upright, advantageous shoot arising from the trunk or branches

Wound dressing– compound applied to a wound or cut