It's cheaper and it works just as good

Justin McDaniel OSU Extension Educator

May 20, 2008 07:10 pm

— How many times have you been sucked in by that line? Only to find out later that if you had only spent that extra dollar or two, you would have had something worth while. But instead you got something that ended up being worthless.
Adjuvant ( Surfactants, stickers, spreaders, drift control) are materials that are added to your sprayer tank to increase the effectiveness of the pesticide you are using. How many times have you heard that “soap works just as good”? Well, it might, but most won't work as well. First, although soaps are essentially surfactants, they are not as concentrated as surfactants manufactured for use with agricultural pesticides.
Household soaps usually have 10- 20% surfactant while Ag. Surfactant has a concentration of 50 to 90 %. This can make a big difference when it comes to enhancing the effectiveness of pesticide activity. Household soaps can also create problems with excessive foaming in the tank and some of these soaps will react with hard water to produce scum and precipitants that can affect pesticide performance. On the other hand most Ag. Surfactants were developed to work in sprayer tank conditions and are not as foamy and will not react with hard water.
Surfactants, or surface acting agents are most often used with herbicides to help a pesticide spread over and penetrate the waxy cuticle of the leaf or to penetrate through the small hairs present on the leaf surface. Since water has a high surface tension it tends to maintain its round, droplet shape when sitting on the surface of the leaf. The surfactant acts to break down this surface tension of the droplet allowing the liquid to spread over the leaf surface. This results in more of the herbicide coming into contact with the leaf and as a result, more of the herbicide gets into the plant.
When you are considering using a surfactant, always consult the label as to the kind of surfactant recommended and to when its addition to the pesticide will help in enhancing the control of the pesticide. Most pesticide companies have spent several years studying how surfactants work with their products and know a lot better than we can guess as to what surfactant will work best with their product. Remember dish washing soap goes in the sink, not the sprayer.