Modern pesticides are supplied in a number of
different physical forms, or formulations.
Products may be in the physical form of a dust, aerosol spray,
wettable powder (see definition below), emulsifiable concentrate (see definition below) or granule and a few others.
The pesticide itself is made of one or more active
ingredients (the poison) plus inactive
carriers like clay or oil. Aerosol sprays
also contain a propellant that pressurizes
the spray can.
Pesticide product names often contain clues to the product's formulation. For example, a dust formulation may have a "D" in the product name such as "Alpine D". Likewise "EC" in the product name would indicate an emulsifiable concentrate or "WP" for wettable powder, and "G" for granules.
Dust (D) formulations are dry with
the active ingredient bound to clay or some other
fine powder, or made entirely from pure active
ingredient such as silica or borate. The problem
with dust formulations is they are difficult to
apply evenly in large areas. A "bulb duster" is often used to apply dust formulated pesticides.
Aerosols sprays (spray can formulations) are popular with homeowners because they are convenient. The active ingredient is
pre-mixed and you don't need a separate pump sprayer.
Aerosols are very expensive, however, on a per
volume basis and so are best used only for small
areas. Also, because they produce a fine mist they tend to be more hazardous from an inhalation standpoint
Wettable powder (WP) pesticides are
dust-like formulations that can be mixed with water, or
sometimes oil, and sprayed through a sprayer of some kind.
Wettable powders are economical and solve the
application problems inherent with dust formulations.
Emulsifiable concentrate (EC) pesticides are formulated from an active ingredient that is not normally soluble in water but in the presence of an "emulsifier" can be diluted with water. Once dilutered they can be applied though some type of sprayer. Emulsifiable concentrates are economical and
generally easy to apply but you will need a separate
The final commonly used formulation is granular
pesticides (G). Granules are course, dry
pellets that are applied through some type of
spreader. Turf and lawn care pesticides are often
applied as granules.