Win the Battle Against Colorado Potato Beetles

As a potato grower, you’re likely no stranger to Colorado potato beetle (CPB). These small, striped pests have a reputation for wreaking havoc on potato fields across the country.

CPB consumes large portions of young leaf tissue. Without sufficient leaf canopy, photosynthesis slows down, leading to the plants drying out, wilting and ultimately losing their leaves. As beetles mature, the damage worsens, making it increasingly difficult for growers to save their crops.

If CPB gets ahead of you, they won’t just nibble at your plants — they’ll attack your bottom line. The good news is you can protect your crops with an effective three-step pest management plan.

Identify Colorado Potato Beetles

Adult CPB have distinct features that make them easy to differentiate from other insects. They’re oval-shaped, about 3/8 inch (10 mm) long, with a yellow-orangish body and 10 black stripes running down their wings. The larvae are smooth, humpbacked and reddish, reaching up to half an inch in length with two rows of black spots along each side.

Larvae feed on potato leaf tissue.

Feeding damage worsens as CPB mature.

Scout for Colorado Potato Beetles

Scouting is one of the best ways to stay ahead of a potential CPB infestation. Here’s how you can monitor your fields effectively:

1. Scout early: CPB emerges from the soil when spring temperatures reach above 50 degrees Fahrenheit in early May. You should begin scouting for adult beetles before the seed is even planted.
2. Watch for larvae: Inspect the undersides of leaves for clusters of yellow eggs. Larvae hatch within 4-14 days and immediately feed on plant leaves. Leaf damage initially appears as small holes, about 1/8” wide.
3. Create an action plan: The moment you begin to see red, spotted larvae crawling around your leaves, that’s your cue to act before they take over.

Manage CPB and Combat Insecticide Resistance

CPB has built up resistance to over 50 different insecticide chemistries. Kiran Shetty, Ph.D., Syngenta technical development lead for potatoes, encourages growers to try a range of approaches to better control CPB and combat resistance.

1. Manage field by field: Tailor your management plan to the location, crop and insect history of the field.
2. Rotate chemistries: Overuse of insecticides can increase the tolerance levels of pests. Use one neonicotinoid seed treatment or soil application per season.
3. Rotate crops: Growers should implement crop rotation between planting seasons, which can significantly reduce outbreak rates and maintain the effectiveness of pest control strategies.
4. Make an action plan: Create a season-long management plan that uses complementary seed treatments and foliar insecticide applications.
5. Use high-quality insecticides: Quality insecticides like Minecto^® Pro are highly effective foliar insecticides that control CPB.

Colorado potato beetles aren’t going away anytime soon, but that doesn’t mean you have to let them take over your operation. By combining crop rotation, tailored field management and chemical rotation, growers can minimize CPB pressure and protect their yields.