adult moth
Photo credit: John Obermeyer

The squash vine borer is an insect that can cause serious damage to cucurbit plants. It is actually a type of clear-winged moth, which is special because—unlike most moths—it flies during the daytime. These moths are quite striking in appearance, with bright orange tufts on their legs, but don’t be fooled—they can harm your garden.


LIFE CYCLE AND TIMING

The squash vine borer spends the winter in the soil as a larva (caterpillar) or pupa (the stage before becoming an adult moth). When the weather warms up, usually around mid-June in our area, they finish developing and come out as adult moths. There are typically two generations (periods of adult activity and egg-laying) in our region.


MONITORING THE PEST

To keep track of when these pests show up, we can use a variety of traps. This year we are deploying HELIOTHIS traps. These traps are baited with a special chemical called a pheromone that smells like a female moth. This scent attracts male moths and pulls them into the trap. By catching the males, we can figure out when the squash vine borers are most active and when to take action to protect plants.


WHY IT MATTERS

As soon as male moths are caught in traps, it means they are ready to mate. Female moths will start laying eggs on plants just a few days later. These eggs hatch in about 6 to 11 days. Once the eggs hatch, the larvae (caterpillars) burrow into the stems of the plants, causing serious damage.


WHAT YOU SHOULD DO

Once you start catching adult moths in your traps, you should begin protecting your plants within 5 days. Use insecticides and apply them at the base of the plant where the stem meets the soil. Keep applying the insecticide until you no longer see moths in the trap.


TRACK SVB ACTIVITY NEAR YOU

Use the database below to find the location closest to your garden or farm. That way, you can track squash vine borer activity in your area and protect your crops at the right time. See this article for management.

Squash Vine Borer Trap Catches - Indiana ONLY

Empty cells indicate that a trap was not collected and emptied. A zero in the cell indicates that no moths were captured during the observation period.