Glossary D Flashcards
Measured at 1.4 meters (4.5 feet) above ground in the United States, Australia (arboriculture), New Zealand, and when using the Guide for Plant Appraisal, 9th edition; at 1.3 meters (4.3 feet) above ground in Australia (forestry), Canada, the European Union, and in UK forestry; and at 1.5 meters (5 feet) above ground in UK arboriculture.
DBH - acronym for tree diameter at breast height.
Dynamic or static climbing system in which a rope is doubled over a branch and the climber utilizes both parts of the line. Contrast with DRT and SRT.
DdRT
a brace formed by threading a lage-threaded screw rod directly into a limb, leader, or trunk but not through the side opposite the installation
dead-end brace
cable-termination devices that must be used to terminate extra-high-strength (EHS) tree support system cable to anchor hardware. May also be used with common-grade cable
dead-end grips (tree grips)
lag-threaded cable anchor or bracing rod that is screwed directly into an undersized, pre-drilled hole in a tree but does not pass through to the other side. Contrast with through-hardware
dead-end hardware
rope sling with a single eye spliced in one end. Also called eye sling, fixed-eye sling, or spliced-eye sling
dead-eye sling
removing dead and dying branches from a tree. Outdated term for crown cleaning, which is more comprehensive
deadwooding
(1) (noun) an area of wood that is undergoing decomposition. (2) (verb) decomposition of organic tissues by fungi or bacteria.
decay
any device used to assess the presence (and often extent) of hidden internal decay
decay detection device
tree or other plant that sheds all of its leaves according to a genetically scheduled cycle as impacted by climate factors (usually during the cold season in temperate zones). Contrast with evergreen.
deciduous
gradually diminishing health or condition of a tree
decline
rounded or spreading growth habit of the tree crown. Contrast with excurrent
decurrent
an imperfection, weakness, or lack of something necessary. In trees, defects are injuries, growth patterns, decay, or other conditions that may reduce the tree’s structural strength.
defect
pertaining to plant nutrition, lack or insufficient quantity of a required element.
deficiency
loss of leaves from a tree or other plant by biological or mechanical means
defoliation
the difference between the daily average temperature and a given temperature base
degree day
splitting apart. Describes the release of seed capsules at maturity.
dehiscent
process of reducing nitrates to nitrogen gases
denitrification
having serrations (teeth) perpendicular to the leaf margin and not pointed forward. Compare to serrate.
dentate
device used to control friction when descending a climbing line. Contrast with ascender
descender
severe drying out. Dehydration.
desiccation
(1) aspects of the landscape or site and the required functions to be served by the plant that must be considered in plant selection. (2) factors considered in the design of equipment.
design criteria
factor by which the rated or minimum breaking strength of a rope or piece of equipment is divided in determining its working-load limit.
design factor
development to a point characterized by a fixed number of leaves or other lateral organs. Contrast with indeterminate growth
determinate growth
process of identifying a disorder by analyzing signs, symptoms, site conditions, patterns, climate, cultural history, and other factors to determine the causative agent(s)
diagnosis
plant with two cotyledons in its embryo; netted or palmate leaf veins; and flowers with three, four, or five petals, or petals in multiples of these numbers. Contrast with monocotyledon.
dicotyledon
condition in which the branches in the tree crown die from the tips toward the center.
dieback
insulating (nonconducting) material
dielectric
process in the development of cells in which they become specialized for various functions..
differentiation
pattern of wood development in which the vessels and vessel sizes are distributed evenly throughout the growth ring. Contrast with ring porous
diffuse porous
a national consensus standards-setting body in Germany.
DIN - Deutsches Institut für Normung
in Germany, standard that deals with plants and planting in the landscape industry….
in Germany, standard that deals with development and maintenance of green areas….
in Germany, standard that deals with the protection of trees on construction sites.
DIN 18916
DIN 18919
DIN 18920
species of plants in which male and female flowers are on separate plants. Contrast with monoecious
dioecious
simple tree cabling system joining two branches or leaders with a single cable. Contrast with box cable system and triangular cable system
direct cable system
any part of the body touching an energized conductor
direct contact
providing clearance by pruning branches that could significantly affect the integrity of utility facilities or other structures, and leaving in place branches that could have little or no effect
directional pruning
wood response of a tree to microorganisms, including bacteria and non-decay-causing fungi, resulting in dead, darkened wood that may be reduced in strength.
discoloration
condition that impairs the performance of one or more vital functions. Usually associated with infectious agents.
disease
combination of factors contributing to the stress or decline of a tree.
disease complex
abnormal condition that impairs the performance of one or more vital functions. Usually associated with noninfectious agents.
disorder
type of friction hitch used in climbing and rigging.
Distel
electric supply lines in a distribution network that carry power from substations to end users. Voltages are generally between 2,400 and 34,500 volts.
distribution lines
portion of the electric supply system that delivers electricity to end users. Includes distribution substations, feeders, primaries, distribution transformers, secondaries, and service lines
distribution network
portion of the transmission and facilities of an electric system that is dedicated to delivering electric energy to an end user.
distribution system
electrical devices that step down primary distribution voltage to secondary voltage supplied to end users.
distribution transformers
taxonomic group below the kingdom level but above the class level.
division phylum
the one stem that grows much larger than all other stems and branches; at least one-third larger than lateral branches nearby.
dominant leader
period of naturally reduced physiological activity in the organs of a plant with the potential for reactivation of growth
dormancy
bud originally developed in a leaf axil and connected to the pith by a bud trace that has not been stimulated to mature and grow. Some buds remain dormant throughout the life of a woody plant…
dormant bud
rope construction consisting of a braided rope within a braided rope, both of which carry part of the load.
double braid
technique consisting of tying one climbing line or two climbing lines into two places in a tree
double crotch
figure-eight knot tied with a double strand of rope.
double figure-eight knot
in arboriculture, the name used for a knot that is commonly used to join two ropes or two ends of the same rope, as when forming a Prusik loop. Grapevine knot
double fisherman’s bend
two half hitches tied in a series
double half hitch
technique consisting of securing a tree section with two load lines in rigging….
double hitch
toothed margin of a leaf, with smaller teeth within the teeth
double serrate
pertaining to a carabiner, requiring two distinct motions to prepare the gate to open.
double-locking
white, fungal-like growth that develops during wet periods, usually on the underside of a leaf
downy mildew
variation on the load-transfer technique in which the load is transferred to a second line and moved to another point, often to a second tree
drift line
applying fertilizer by drilling holes in the soil within the root zone. Contrast with broadcast fertilization and liquid fertilization
drill-hole fertilization
D-shaped metal rings on a climber’s saddle for attaching ropes and snaps.
D-rings
method of minimizing evaporation and runoff by applying small amounts of water through small emitters….
drip irrigation
imaginary line defined by the branch spread of a single plant or group of plants.
drip line
branch-removal technique consisting of an undercut and then a top cut, usually made farther out on the branch, or with a chain saw, directly over the undercut.
drop cut
rope used to secure the weight of a limb in rigging; load line.
drop line
technique used to start a chain saw by pushing the saw away from the body and simultaneously pulling the start cord.
drop start
predetermined area where cut branches or wood sections will be dropped or lowered from a tree. See landing zone
drop zone
(obsolete) term for a method of reducing the height of a tree. The general rule for cuts is that leaders should be cut back to a lateral capable of assuming apical dominance, if possible, usually at least one-third the diameter of the leader. See reduction.
drop-crotch pruning
period of unusually low precipitation
drought
Climbing system in which two separate ropes and two separate anchor points are utilized. Contrast with DdRT and SRT..
DRT - double rope technique.
method of tying the root ball of a balled-and-burlapped tree for moving
drum lace
stony seed inside a fleshy covering (for example, cherry and peach).
drupe
drought adaptation of acclimated plants that become dormant during the dry season
dry season dormancy
legal obligation that requires an individual to apply reasonable actions when performing tasks that may potentially harm others
duty of care
any of several cabling systems that utilize nonrigid materials (usually rope of various constructions and elasticity) for tree support systems.
dynamic cable system
forces created by a moving load. Load that changes with time and motion. Contrast with static load
dynamic load
study of how objects move under the action of forces.
dynamics
instrument for measuring mechanical force or power
dynamometer
