An emulsifier is added to cause oil to form tiny globules, which disperse in water. The formulation then will mix readily with water for proper application. Emulsifiable concentrates usually contain between 2 and 8 pounds of active ingredient per gallon. In addition, the gelling process reduces the need for nonaqueous solvents compared to standard nonaqueous EC-type formulation processes. Suspensions of wettable powders appear cloudy.
Wettable powders are nearly insoluble and require agitation to remain in suspension.
Atrazine and linuron are formulated as wettable powders. Once the powder is dissolved, the spray mixture requires no additional mixing or agitation. However, few pesticides are available as soluble powders because most pesticide active ingredients are not very soluble in water. Nearly insoluble, they require agitation to remain in suspension. Atrazine and linuron also are formulated as dry flowables.