Agriculture Reference
In-Depth Information
tation after they are mixed. Water-soluble concentrates are often liquid, salt,
or amine solutions (e.g., Touchdown
38-SL a water-soluble liquid).
6.
Oil Solutions
The active ingredient in oil solutions is formulated either with oil or with
some other organic solvent. The formulation may be highly concentrated so
that further dilution with oil is required before application or it may be sold in
a dilute form ready for application. In either case, they are true solutions and
agitation is not necessary to maintain them.
In their commonest form, oil solutions are the ready-to-use household and
garden insecticide sprays sold in a variety of bottles, cans, and plastic contain-
ers, all usually equipped with a handy spray atomizer. Not to be confused
with aerosols, these sprays are intended to be used directly on pests or places
they frequent.
Oil solutions may be used as roadside weed sprays, for marshes and stand-
ing pools to control mosquito larvae, in fogging machines for mosquito and
fly abatement programs, or for household insect sprays purchased in super-
markets. Commercially they may be sold as oil concentrates of the pesticide
to be diluted with kerosene or diesel fuel before application or in the dilute,
ready-to-use form. In either case, the compound is dissolved in oil and is ap-
plied as an oil spray; it contains no emulsifier or wetting agent.
As with the emulsifiable concentrates, oil solution may cause damage to
vegetation because of the high concentration of solvent; they also may cause
significant deterioration of rubber sprayer components. The high-concentrate
solutions must be handled with particular caution.
Examples of oil solutions are the dormant oils which are used to control
scale insects in trees (see
Figure 4.4
)
.
7.
Flowables or Sprayable Suspensions
Flowables (F, FL), sometimes called water-dispersible suspensions, are
particularly useful formulations for active ingredients that are not soluble in
either water or the more commonly available organic solvents. The active
ingredient is impregnated on a diluent such as clay, which is then milled to an
extremely fine powder. The powder is then suspended in a small amount of
liquid so that the resulting formulation is thick, like paste or cream. Flow-
ables are essentially WPs in suspension that you can measure by volume.
They combine the benefits of both WPs and ECs and are becoming increas-
ingly popular. They are mixed with water or liquid fertilizer to form suspen-
sions which require moderate agitation in the spray tank. Because they are
