Corn earworm is a big problem for gardeners across the country. An old-fashioned yet effective organic control is to apply a several drops of mineral oil on the corn silks (where the adult moths lay their eggs). As the eggs hatch, the oil smothers the emerging larvae, which would otherwise eat their way to the tip of the ear to feast on kernels. When combined with Bacillus thuriengensis (B.t.), the oil is even more effective, but the mixture can be difficult to apply with a regular dropper.
Now researchers at the University of Massachusetts and Hampshire College have developed a tool that makes applying the pesticide easier. Zea-Later consists of an ergonomic hand-held applicator connected by a clear plastic tube to a 2-liter tank that you can attach to your belt. The handle is molded to fit your hand comfortably. When you pull the "trigger" to release a dose of oil and B.t., you use all your fingers together thus reducing hand fatigue. To apply the pesticide, place the pointed tip at the center of the ear and push it slightly into the ear tip. Squirt the oil so it reaches into the ear tip. One tankful treats about one-quarter acre of corn. The best time to apply oil is 4 to 6 days after silk begins to grow, or 2 to 4 days after the silk is full-grown.
For more information on Zea-Later go to the University of Massachusetts Web site .
Article published on July 19, 2005.