Glossary A Flashcards
abiotic
nonliving
abiotic disorder
plant malady caused by nonliving, environmental, or man-made agents (contrast with biotic disorder).
abscisic acid (ABA)
plant hormone that stimulates stomatal closure and promotes seed and bud dormancy. Inhibits shoot growth but may promote root growth. Plays a role in wounding responses and in abscission of leaves and fruit.
abscission
leaf or fruit drop induced by hormonal changes.
abscission zone
area at the base of the petiole where cellular breakdown leads to leaf and fruit drop.
absorbing roots
fine, fibrous roots that take up water and minerals. Most absorbing roots are within the top 12 inches (30 cm) of soil.
absorption
taking up (contrast with adsorption).
adsorption
adhesion on contact of the molecules of gases, dissolved substances, or liquids to the surface of solids or liquids with which they are in contact (contrast with absorption).
acceleration
rate of change of the velocity of an object. Acceleration is a vector quantity (see vector and velocity).
acceptable risk
the degree or amount of risk that the owner, manager, or controllong authority is willing to accept.
access line
1) second climbing line hung in a tree in case it is needed to reach a victim in an emergency. 2) climbing line installed in a tree to gain access to, but not used to work, the tree.
access route
defined entrance and exit route for a property during construction, tree work, or landscape operations.
acclimation
physiological adaptation process of plants and other living organisms to a climate or environment different from their native environment or where originally grown.
acid
having a pH less than 7.0 (contrast with alkaline).
acidity
state or quality of being acid (contrast with alkalinity; see pH).
acorn
characteristic fruit of plant species belonging to the Quercus genus.
actinomycetes
group of soil bacteria resembling fungi. Actinomycetes play a role in the decomposition of organic matter and the release of mineral elements.
action
pertaining to carabiners and snaps, the number of distinct motions for the gate to be opened. A nonlocking carabiner is single action, requiring one movement for the gate to be opened.
action threshold
pest population or plant damage level that requires action to prevent irreversible or unacceptable physiological and/or aesthetic harm (see economic threshold).
acuminate
term describing leaves that taper sharply at their tip (apex).
acute
disorder or disease that occurs suddenly or over a short period of time (contrast with chronic).
adaptability
genetic ability of plants and other living organisms to adjust or acclimate to different environments.
adhesion
force of attraction between two different materials; in soils, it is the attraction of water molecules to soil particles.
adjustable balancer
adjustable rigging sling used to balance tree limbs being removed in rigging operations.
adpressed
in close, tight proximity. Pressed close to or lying flat against something. Appressed
an assessment performed to provide detailed information about specific tree parts, defects, or site conditions. Specialized equipment, data collection and analysis, and/or expertise are usually required.
advanced assessment
arising from parts of the root or stem and having no connection to apical meristems.
adventitious
bud arising from a place other than a leaf axil or shoot tip, usually as a result of hormonal triggers.
adventitious bud
roots arising from roots or stems and having no connection to apical meristems.
adventitious roots
shoot that develops from an adventitious bud….
adventitious shoot
provision of air to the soil to alleviate soil compaction and improve its structure.
aeration
set of holes or trenches created in the tree’s or other plant’s root area to improve oxygen availability to the roots and gas exchange with the atmosphere. Aeration systems sometimes include an underground arrangement of porous pipes or tubing.
aeration system
inspection undertaken from a plane or helicopter; often used by electric utilities to monitor tree growth near electric transmission lines.
aerial (airborne) patrol
system of reducing the physical hanging space of aboveground electrical conductors.
aerial bundle cable (ABC)
1) a device, with booms and a bucket, for elevating a worker to the proximity of a tree’s crown; may be mounted on a truck or other vehicle or be towed or self-propelled (also known as a mini-lift). 2) a self-propelled device such as a scissor lift, with an elevating platform but without side reach for placing a worker in the proximity of a tree’s crown; may be used for hedges or interior trees. In the United Kingdom, such devices are called a mobile elevated work platform (MEWP).
aerial device (aerial lift device)
inspection of the upper tree parts not readily accessed from the ground; typically done by climbing or from an aerial lift.
aerial inspection
method of bringing an injured worker down from a tree or aerial lift device
aerial rescue
Above ground roots. Usually adventitious in nature and sometimes having unique adaptive functions
aerial roots
pleasing to the senses, visually or otherwise. Artistic.
aesthetic
1) close cluster or mix of small particles of soil and/or organic matter of varying size that are bonded together. 2) sand, gravel, or small rocks in soil; and/or sand, gravel, or small rocks used under paved surfaces. 3) clusters of flowers or fruits that appear as a single unit. 4) individual tree crowns that form a canopy
aggregate