Glossary H Flashcards
characteristic form or manner of growth….
habit
an environment suitable for sustaining a population of a given organism….
habitat
simple knot used to temporarily attach a line to an object. Also used as a backup in combination with other knots….
half hitch
plants that tolerate soils with a high concentration of salts….
halophytes
a small, handheld magnifying glass….
hand lens
tool used for pruning twigs of less than 1/2 inch (1.27 cm) diameter. Contrast with secateurs. …
hand pruning shears
broken or cut branch that is hanging in a tree….
hanger
protective hat made of a rigid material that must be worn when climbing and working on trees….
hard hat
rope manufactured with tightly wound strands, making it stiffer than standard lay or soft lay ropes….
hard lay rope
plant tissue that is acclimated to the cold or a new environment….
hardened off
genetically determined ability of a plant to survive low temperatures….
hardiness
compacted soil layer nearly impervious to water, air, and roots….
hardpan
the constructed inanimate elements of a landscape, such as walls, pathways, and seats made of wood, stone, and/or other materials….
hardscape
(1) wood of an angiosperm tree as distinguished from that of a conifer; broadleaf tree. (2) refering to an angiosperm, or broadleaf tree.
hardwood
device used to clasp and hold cables….
Haven grip
a situation or condition that may result in personal injury, property damage, or disruption of human activities. (1) in tree management, a tree or tree part that has a high liklihood of failure and causing damage or injury. (2) in tree care or forestry operations, the presence of a condition or situation that may cause harm or injury to workers or others.
hazard
systematic process of identifying hazards. See risk assessment….
hazard assessment
the process of managing, reducing, or eliminating an identified hazard. …
hazard mitigation
type of pruning to remove dead, severely decayed, split, or other unsafe branches….
hazard reduction pruning
cutting a shoot back to a bud or cutting branches back to buds, stubs, or lateral branches not large enough to assume apical dominance. Cutting an older branch or stem back to a stub in order to meet a structural objective.
heading (heading back)
a physiological, regenerative process not known to occur in plants….
healing
any of several types of fungal decay of tree heartwood, often beginning with infected wounds in the living portions of wood tissue….
heart rot (aka. heartwood rot)
wood that is altered (inward) from sapwood and provides chemical defense against decay-causing organisms and continues to provide structural strength to the trunk. Trees may or may not have heartwood. Contrast with sapwood.
heartwood
an urban area that is warmer than its surrounding rural areas due to urban activities and greater heat retention by urban structures and development….
heat island effect
ability of a plant to endure high temperatures
heat tolerance
tool used to trim hedges….
hedge shears
chemical compounds that kill vegetation….
herbicides
an animal the feeds primarily on plants….
herbivore
lines with voltages greater than a specified amount, typically in excess of 60,000 volts, depending on the utility….
high voltage lines
strip of uncut wood fibers created between the face cut or notch and the back cut that helps control direction in tree felling or limb removal. Holding wood.
hinge
sequence of cuts used to control the direction of a limb being removed….
hinge cut
(1) type of knot made when a rope is secured around an object or its own standing part. Contrast with bend. (2) a mechanical device for connecting a towing vehicle to a trailed or towed vehicle or implement.
hitch
section of wood located between the face cut and the back cut that helps direct where the tree will fall. See hinge….
holding wood
rope construction consisting of a braided rope with no core….
hollow braid
sugary substance secreted by certain insects, including aphids and some scale insects, when feeding on plants….
honeydew
layer of soil within the soil profile….
horizon
boring, with special machinery, below the surface of the ground without an open trench. Alternative for installation of underground utilities that avoids cutting of tree roots or damage to hardscape or existing utilities. Contrast with radial trenching, trenching, and tunneling.
horizontal boring
highly refined petroleum oils that may be applied to plants to smother certain insects and other pests by disrupting their respiration….
horticultural oils
art and science of growing, handling, and processing fruits, vegetables, and ornamental plants….
horticulture
living organism from which a parasite obtains nutrition….
host
in the United Kingdom, the Health and Safety Executive, which is the government agency that deals with health and safety in the workplace….
HSE
felling notch that is horizontal on the top and angled on the bottom. Also called Humboldt scarf or reverse scarf. Contrast with conventional notch and open-face notch….
Humboldt notch
dark-colored, stable form of organic matter that remains after most of plant or animal residues have decomposed….
humus
plant resulting from a cross between two or more other plants that are more or less alike….
hybrid
crystalline polymers which absorb water and, if needed, can be added to the soil to increase its water holding capacity….
hydrogels
study of the properties, distribution, and effects of water on the earth’s surface, underground, and in the atmosphere….
hydrology
the physical or chemical property of a molecule or substance that is attracted to water (and may be dissolved in water)….
hydrophylic
the physical or chemical property of a molecule or substance that is attracted to water (and may be dissolved in water)….
hydrophilic
condition of highly organic soil after it has completely dried and its chemical composition repels water rather than absorbing it….
hydrophobic
grouping plants in a landscape according to their water requirements….
hydrozoning
retained water that is held too tightly in soil for uptake by plants….
hygroscopic
