Environmental Engineering Reference
In-Depth Information
Mower, vertical (verti-cutter):
A device with blades that cut vertically
into the turf canopy to sever lateral stems, thin grass and dethatch.
Nematicide:
A pesticide used to control nematodes.
Nematodes:
A group of soil-borne, microscopic, worms, some of which
attack the root systems of plants.
One-third rule:
The mowing rule that specifies that no more than one-
third of the total leaf area be removed at any one cutting.
Overseeding:
The application of additional turf-grass seed to existing
turf.
Peat moss:
A commonly-used organic amendment consisting largely
of undecomposed (or only slightly decomposed) organic matter which
accumulates under conditions of excessive moisture.
Perched water table:
Layering of soil designed to retain moisture in a
surface layer above a coarser and better-drained lower layer.
Percolation:
The downward movement of water through the soil.
Perennial:
A plant that can reproduce several times over several grow-
ing seasons.
Pest:
In turf-grass management, any living organism that competes
with turf-grass plants for nutrients, light, water, air or space, or that
otherwise adversely affects turf-grass performance, for example by caus-
ing disease.
Pesticide:
A chemical agent used to kill pests.
Plant growth regulator (PGR):
A chemical agent applied to plants to
suppress their growth.
Plugging:
The process of installing turf-grass by planting rooted pieces
or 'plugs' of live turf, which will be encouraged to spread over a desired
area.
Polystand:
An area of turf-grass made up of more than one species of
plant.
Porosity, soil:
The amount of air space between the particles of soil,
expressed as a percentage of the volume of soil not occupied by solid
particles.
Pregermination:
A method used to reduce seed germination time in
which seed is soaked or placed in a moist environment to encourage
partial germination, then planted as soon as possible to prevent desicca-
tion.
