Dictionary of LA Flashcards
A1 horizon
A soil layer that is a subhorizon of the A horizon, distinguishable by its darker color from the rest of the A horizon due to a higher content of organic matter.
A2 horizon
A soil layer that is a subhorizon of the A horizon, distinguishable by its lighter color from the rest of the A horizon due to a lack of organic matter because of leaching or eluviation.
A3 horizon
A soil layer that is a subhorizon of the A horizon, similar to the A2 horizon, but also transitional to the B horizon, with visually distinguishable changes from either.
AAA
Abbreviation for the American Arbitration Association.
AAN
Abbreviation for the American Association of Nurserymen (now known as the ANLA).
AAN Standards
The American Standard for
Nursery Stock, as published by the American
Association of Nurserymen (AAN).
AARS
Abbreviation for All-American Rose
Selections.
AAS
Abbreviation for All-American Selection.
abacus A slab or division that forms the uppermost portion of the capital of a column, usually
wider than the column.
abandonment
A word often used in contract
law to describe the failure of both parties to
abide by the terms of a contract.
abate
Removal of material, usually in making a
design or producing a product from wood, metal,
stone, etc. In metal work, this may be descriptive
of the beating or pounding of a design into the
material.
abat-vent
Angled members with some space
between them in an opening of an exterior wall
or fence used for access to light while blocking
wind and screening views. See also louver
abaxial
In botanical terms, the side away from
the axis.
ABC
- Abbreviation for aggregate base
course. - A reference to a type of soil profile.
- Abbreviation for Associated
Builders and Contractors
ABC soil
A mature soil profile that contains
the three major soil horizons.
aberrant
A descriptive term given to individual
plants or species different in some way from the
group they are associated with.
abiotic
Not living
abortive
In botanical terms, an imperfectly
developed portion of a plant
Abram’s law
The strength of concrete is
directly influenced by the ratio of water to
cement.
abrasion
The act of wearing away by friction.
abrasive
A substance harder than the material
it is used against in rubbing or grinding to create friction and wear away the softer material. Examples of useful abrasives are diamonds, carbide
steel, metal shot, and sand (as with sandpaper).
abrasive surface
A surface that is roughened for safety, such as the front tread of a stair.
abrevoir
A space, gap, or joint between stones that is filled with cement or mortar.
abscisic acid
A growth-inhibiting plant hormone, which also promotes leaf fall (abscission), the formation of potato tubers, and the change to dormancy in leaf buds.
abscission
The natural separation of fruit, leaves, or flowers from a plant at a special area of tissue.
abscission layer
The layer of tissue in a plant
that facilitates the dropping of fruit, flowers, and
leaves that cease to function.
absolute pressure
In pumping references, the
total pressure above absolute zero.
absorbed moisture
Water that has been
absorbed into the pore spaces of a solid such as
soil or wood.
absorber
- That portion of a solar collector
that collects and absorbs radiant heat energy. - A material that collects and holds pollutants
such as oil from water runoff, usually within a
catch basin or an oil separator. - A device used
to arrest the shock of water hammer.
absorbing well or dry well or waste well
A well collecting surface waters, providing for the
water to be dispensed and absorbed into the
ground.
absorption
- A process by which a gas and/or
liquid enters into a solid material. This occurs
through pores in a porous solid material. This
process is usually accompanied by a chemical
and/or physical change of the solid material. - The process by which radiant energy is converted to other forms of energy.
- The increase
in weight of a solid material due to the process
described in (1.) - The increased weight of a
tile or brick when immersed into boiling water
or cold water for a determined period of time.
This weight change is usually expressed as a percentage of the weight of the dry weight. - A
process where one substance adheres to the surface of another
absorption bed
An excavation that is filled
with coarse aggregate and has a piping system for
distribution of septic tank effluent.
ABS plastic or ABS pipe
A plastic of acrylonitrile butadiene styrene often used to make pipe that is resistant to impact, heat, chemicals, and freeze-thaw. It is softer than PVC plastic and
usually black.
abut
- To make contiguous or to make a contact point.
- In real estate, two properties with
a common property line.
abutment
The part of a structure such as a
bridge or an arch that bears the weight of the
span and is usually made of masonry or concrete.
abuttals
Those boundaries of one piece of land
that are in common with adjacent pieces of land.
abutting joint
A joint between two pieces of
wood, where the direction of the grain in one
piece of wood is at an angle (usually 90°) to the
grain in the other.
AC, ac, a-c, a.c.
- Abbreviation for acre(s).
2. Abbreviation for alternating current
ACA
Abbreviation for ammoniacal copper
arsenate. A thorn-like or spike-like protrusion.
acaulescent
In botanical terms, a plant or leaf
that is without a stem, or appears to be without a
stem.
ACC
Abbreviation for acid copper chromate.
accelerated erosion
The movement of
earthen particles in water runoff increased by
human activities influencing the land. Activities causing increased erosion include removal of
vegetation, loosening of soil, concentrating
areas of runoff, or interruption of natural
drainage patterns.
accelerator
A material or substance added to
concrete, grout, or mortar to increase its rate of
hardening, and/or decrease its setting time.
access
A way of vehicular, pedestrian, or other
approach, entry, or exit.
access door
A door that provides access to
equipment for maintenance, inspection, or
repair.
access panel or access plate
A removable
panel or plate (usually secured with screws or
bolts) in a frame that is usually mounted in a
ceiling or wall and provides access to concealed
items or equipment. It permits inspection of an
otherwise inaccessible area. Wires and/or pipes
for irrigation systems or pumps are sometimes
concealed behind these panels in buildings.
They are also sometimes designed into park
restrooms and pavilions for infrequent access to
areas in ceilings or behind walls.
accessibility standards
Parameters and recommendations regarding accessibility of handicapped persons to walks, structures, etc. See
Americans with Disabilities Act and Uniform
Federal Accessibility Standards.
accessible
- Easily accessed.
- Reachable by
removal of a cover, panel, plate, or similar
obstruction. - Easily accessed by those disabled
in wheelchairs or walkers.
accessible means of egress
A path of travel,
usable by a person who has impaired mobility,
that leads to a public way.
accessory building
A building with a secondary use to that of the main building located
on the same plot. Refer to local jurisdictional
agencies for their definition.
accessory structure
A subordinate structure
detached from, but located near, a principal
building. Accessory structures usually include
garages, decks, fences, sheds, etc.
acclivity
A slope above; an upward slope.
accouplement
Placement of posts, columns,
or pillars in sets of two (paired).
accrescent
A botanical term, something that
increases in size with age.
ACD
Abbreviation for an automatic closing
device.
ACE
Abbreviation for Agricultural Conservation Easement.
acerose
In botanical terms, a plant part shaped
like a needle or having a needle-like tip.
acetone
A highly volatile solvent often used in
lacquers, paint removers, thinners, etc.
acetylene
A colorless gas, that when mixed
with oxygen, burns at a temperature of about
3500°C; used in welding.
acetylene torch
A metal-cutting and welding
instrument that operates on compressed acetylene (a colorless hydrocarbon) and oxygen.
achene
In botanical terms, a small, dry, onecelled, one-seeded, indehiscent fruit. In technical terms, it does not include those fruits with
specialized features such as a samara, caryopsis,
nut, or utricle.
achlamydeous
A flower without a perianth
outside envelope, calyx, corolla
achromatic color
White light; a color that
does not elicit hue
ACI
Abbreviation for American Concrete
Institute.
acicular
In botanical terms, needle-shaped.
acid
- In reference to soil, this indicates a pH
below 7.0 (neutral). 2. A chemical substance
capable of releasing excess protons (hydrogen
ions).
acid copper chromate (ACC)
A waterborne salt preservative for wood. Wood must be
pressure treated for this preservative to be effective. It is highly recommended by experts as it is
odorless, clean, does not leach, and its color can
be masked easily when dry by painting or applying a solid color stain. This stain is not only good
for preserving wood above grade, but can also be
used for preservation of wood to be placed
underground.
acid etched
A reference to a metallic surface,
glass, or concrete that has been treated in an
acid bath to provide a rough surface or to
remove a portion of its surface
acidic
- Soil or water with a pH less than 7.0.Some only consider acidic to be 6.6 or less.
- Igneous rocks containing more than 65%
silica.
acidity
The measure of a substance’s pH below
neutral (7.0).
acid rain
Any rain that contains sulfur dioxide.
acid soil
Soil having an acid reaction. It is usually in reference to a soil having a pH value of
less than 6.6, but is technically applicable to any
value lower than 7.0, which is neutral. These
soils are common in areas of high rainfall. The
most common cure for highly acidic soils is the
addition of lime.
acisculis
An old term for a small mason’s pick,
with a flat face and pointed peen.
ACM
Abbreviation for asbestos-containing
material. Any material with over 1% asbestos
content.
AC pipe
Asbestos-cement pipe that was commonly used for buried pipelines. It combines
strength with light weight and is immune to rust
and corrosion. It is no longer made because of
the health hazards associated with asbestos.
acquiescence
- An act of concurrence by
adjoining property owners that resolves a
boundary dispute or establishes a common
boundary, where the definite or more accurate
position of same has not or cannot be defined by
survey. 2. The tacit consent of one owner, by
not making a formal objection, to what might
be an encroachment by an adjoining property
owner over a questionable boundary.
acre
English or U.S. measurement of area equal
to 4840 sq yd; 43,560 sq ft; 0.405 hectare;
4046.85 sq m.
acre-foot
- A reference to a quantity of water
required to cover one acre to a depth of one foot.
acetylene - A quantity of any material equal to the
amount required to cover an acre one foot deep.
acrid
Sharply bitter, unpleasantly pungent, or
harsh in smell or taste.
acropodium
- A raised pedestal bearing a
statue. - The lowest member of a pedestal of a
statue.
acrylonitrile butadiene styrene (ABS)
A
plastic formulated into piping that is used primarily in landscape work for drainage systems,
storm sewers, irrigation systems, and underground electrical conduits. It is softer and much
more bendable than PVC.
ACS
Abbreviation for actual.
AC soil
An immature, incomplete soil profile
with only the A and C horizons present, and no
B horizon. These young soils commonly develop
from alluvium or on slopes.
actinomycetes
A group of soil microorganisms intermediate between fungi and bacteria.
They may be filamentous much like fungi, and
yet produce spores similar to bacteria. They are
microscopic in size and are usually the source of
the fresh, uniquely pleasant odor of newly tilled
soil. They are active in decomposition, especially of cellulose.
activated sludge
- A recycled, dried product
of municipal sewage treatment plants. It has
higher concentrations of nutrients than composted sludge with a rating of approximately
6-3-0.5 for primary nutrients. It is usually sold in
a dry, granular form as a general-purpose fertilizer that does not burn, and is slow to release its
nutrients. The long-term effects of using sewage
sludge are still under investigation. Heavy metals such as cadmium may be present in the soil
where sewage sludge has been used, and they
may build up over time. There are possible negative effects depending on the content and origin of the sludge used. 2. Sewage within aerated
wastewater treatment basins and its associated
complex variety of living microorganisms. After
settling, a portion of this microbial sludge is
recycled to influent of the treatment system.
Microbes there continue to grow. The remaining
activated sludge is removed from the treatment
system and disposed of another way
active earth pressure
The horizontal pressure of retained earth in a horizontal direction.
active layer
The surface layer in climates
where permafrost exists. It is characterized by
freezing and thawing.
active open space
Land designated or reserved
for recreational facilities such as swimming pools,
ball fields, court games, picnic tables, exercise
courses, playgrounds, ice skating, etc.
active pressure
The force exerted by retained
earth.
active recreation
Athletic activities, or those
activities of leisure requiring physical effort and
often requiring equipment. This type of activity
usually takes place at prescribed places, sites, or
fields. It includes such activities as swimming,
tennis, other court games, baseball, other field
sports, golf, playground activities, jogging, rowing, etc. See also passive recreation.
active sludge
A sludge that is rich in destructive bacteria; useful in breaking down fresh
sewage.
active solar energy system
A system that
collects solar energy and distributes that energy
by mechanical devices such as fans or pumps
that obtain their energy from a conventional
source (not from solar energy).
Act of God
An unexpected event not controllable by human influence.
actual
This word is often used in specifying
weight amounts of a specific nutrient in a fertilizer to be applied. This can be determined by
taking the percentage of the specific nutrient in
the fertilizer mix and multiplying it by the
weight of the fertilizer being used.
actual start of construction
The first placement of a permanent construction fixture on site.
aculeate
In botanical terms, prickly or beset
with prickles.
acuminate
In botanical terms, sharply tapering
to a slender point. (Compare with retuse, cuspidate, aristate, emarginate, acute, mucronate,
obtuse.)
acute
In botanical terms, pointed, or ending in a
point less than a right angle. (Compare with
retuse, cuspidate, aristate, acuminate, emarginate,
mucronate, obtuse.)
acute angle
Any angle measuring less than 90°.
acute arch or lancet arch
A sharply pointed
arch whose centers are farther apart than the
width of the arch.
AD, ad
- Abbreviation for air dried. 2. Abbreviation for access door. 3. Abbreviation for
area drain. 4. Abbreviation for as drawn. 5. A
designation of the surface grades of two sides of a
piece of lumber, especially plywood. 6. A Latin
prefix used in botanical terms meaning to or
toward.
ADA
Abbreviation for Americans with Disabilities Act.
adapt
To make suitable for a particular purpose,
requirement, or condition, by means of modifications or changes.
adapter
- A fitting or part that facilitates different types (copper, PVC, polyethylene, galvanized) or sizes of pipe to be connected together.
- A device manufactured for the purpose of
connecting tubing or equipment (especially
electric) that is of different size, connection
type, or design.
adaptive use
The extensive alteration, restoration, and/or renovation of an existing structure
or building so that it will serve a new purpose.
ADD, add
- Abbreviation for addendum.
2. Abbreviation for addition.
addendum
A change or revision to drawings,
specifications, or other information on a project
out for bid, which has an effect on bids. It occurs
before receipt of bids, and is usually stated in letter form that ethically should be delivered to all
bidders (in fairness) with the drawings or papers
indicating the change so as to allow understanding in comparison of bids. These changes become a part of construction documents for
contract purposes.
addition
- Construction that increases the
height or floor area of an existing building or
adds such items as a porch or attached garage. - The increase to an existing contract amount.
The professional procedure for accommodating
such a change is a change order.
additive
A substance added to another substance to improve its characteristics such as
those used in paints, plasters, mortars, etc. See
also admixture.
additive alternate
An option on a bid for
more services or materials not in the base bid,
showing increased costs, if any, associated with
the option.
ADF
Abbreviation with reference to shipping
lumber meaning after deducting freight.
ADH, adh
Abbreviation for adhesive.
adhesion
The physical attraction of unlike substances to one another. This is the force that
holds water molecules in soil-to-water interfaces
so that all water does not drain from soil after
saturation. This water is held in mesopores and
micropores, but there is not enough adhesion
force to hold water in the larger macropores.
adhesive
A substance that bonds to materials
placed together, holding them in place.
Adj., adj
Abbreviation for adjustable.
adjoining grade elevation
The average elevation of the finish grade adjoining all exterior
walls of a building or structure calculated from
grade elevations taken at intervals (usually 10 ft
or 3 m) around the perimeter of the building.
adjustable hanger
An apparatus for holding
pipes or equipment hung from structures, which
has the ability to change the elevation of the
pipe or device held without detachment of the
apparatus from the structure.
adjustable wrench
A wrench with an adjustable portion of its jaw movable by a knurled
screw to facilitate grasping objects of varying sizes
(e.g., pipe wrench, crescent wrench).
adjusted sodium adsorption ratio
An
index of permeability problems with regard to
water quality
admixture
A material or chemical added to a
concrete mix to accelerate cure, retard curing,
repel water, or change its normal properties.
adobe
- Clay used in making adobe brick.
2. Any unfired brick.