Have you ever wondered how striped cucumber beetles manage to find your cucurbits every year? Striped cucumber beetles rely on sight and smell to find food. They are particularly attracted to the color yellow and to scents produced by cucurbit flowers and male striped cucumber beetles. This summer we studied how we could use lures that imitate cucurbit flowers and live beetles for mass trapping with yellow gallon jugs.
On one farm, 16 traps captured 2,363 striped cucumber beetles from late May through early September (Figure 1). The vast majority of these beetles were captured in May and August. In May, the beetles were most attracted to the control jugs, but in August, beetles preferred jugs containing live beetles and floral lures.
If you place traps early in the season—before or as striped cucumber beetles begin to emerge—we recommend using only yellow jugs without any lures or live beetles. If you trap toward the end of the season to reduce overwintering beetles, we recommend using yellow jugs with the floral lure and potentially live beetles as well, if possible.
Materials needed:
Gallon jugs traps
Gallon jugs
Yellow high gloss spray paint
Drill with 7/32” bit
Dish soap
Water
Stake
Zip ties or wire
Floral lure, string, small plastic bag (optional)
Live beetle containers (optional)
Container
Hot glue
Knife
Rope
High tunnel mesh
Striped cucumber beetles
Beetle food (cucurbit leaf, flower or fruit)
Directions:
Drill two rows of ten holes along each side of the jug. Based on our experience last summer, we recommend making the holes about halfway up from the bottom of the jug, so that the jugs could hold more water and reduce spillage. Cover all sides of the jug with yellow high-gloss spray paint.
Place the stakes approximately 30 feet apart and use zip ties to hold the jugs several feet from the ground. Add soapy water to the jugs. The soap will break the surface tension and help the insects drown (Figure 2).
For the floral lures, use the corn rootworm lure (TRE 8276) from TRÉCÉ, Inc. (https://www.trece.com/). These lures are available for $2.50 each and last for one month. The lures should be hung from the inside of the jug with a piece string. If you have difficulty getting the lure through the mouth of the jug, the lures can be cut in half and placed in a small plastic bag.
For the live beetle traps, cut out two sides of a plastic container and hot glue mesh in its place to provide ventilation (Figure 3). Drill two holes near the top to attach a rope for hanging and use hot glue to seal any gaps. Each trap should contain ten striped cucumber beetles collected from a field. While we used sugar water to keep the beetle bait alive, a cucurbit leaf, flower, or fruit could be used instead.
Our traps were based on those developed by Dr. Jaime Piñero at the University of Missouri. For more information on their traps and study go to: https://ipm.missouri.edu/IPCM/2016/6/A-novel-mass-trapping-system-to-control-cucumber-beetles-in-cucurbit-crops/.
Figure 1. Striped cucumber beetles trapped on one farm throughout one season
Figure 2. Beetles are attracted to the color yellow and to the lures within the jugs. Once they find their way inside, they have difficulty finding their way out, eventually falling into the soapy water to die.
Figure 3. Gallon jug trap plus a container for live striped cucumber beetles. Two sides of the container were removed and replaced with high tunnel mesh to provide ventilation.