AgronomyInsectsNo Margin of Error to Control the Colorado Potato Beetle

No Margin of Error to Control the Colorado Potato Beetle


  1. Neonicotinoids have been used in Ontario for 26 years to control the Colorado potato beetle (CPB) but relying on one mode of action at planting accelerates the development of resistance. Detection of CPBs hot spots in the province have been due to untreated areas in fields, the result of plugged nozzles, or beetles moving into the crop late in the season beyond the active life of the insecticide.
  2. Test any suspicious CPB populations with a dip test/spray test, which will tell you in 24 hours if the beetles are less susceptible or resistant.
  3. Actara (thiamethoxam) and Titan (clothianidin) are commonly used at planting as seed treatments or in- furrow treatments (Titan in-furrow is allowed until March 2023). Both insecticides will also control potato leafhopper and aphids. Potato flea beetles are controlled by Titan, but somehow, flea beetle control does not appear in the Actara label. Admire (imidacloprid) is a weaker molecule and does not provide control for as long as Actara or Titan.
  4. Use neonicotinoids at the high labelled rate at planting, either as a seed treatment or in-furrow. This should provide control for 60 days, long enough to act on the second generation of beetles, which usually emerges at the beginning of July. If you pre-cut and treat, deduct the number of days that the pre-cut seed was kept in storage before planting from the 60 days.
  5. If an insecticide is needed to control the second generation of beetles, use one with a different mode of action. Rotating modes of action is essential to managing insecticide resistance. Vayego (tetraniliprole) is a good option. It controls all the CPB stages as well as flea beetles and European corn borers. Vayego also suppresses aphids.
  6. Many of the other insecticide options are most effective on small larvae. Scouting is essential to time applications to when the CPBs are at this susceptible life stage. Also, many of the other insecticides have limited efficacy against other potato insects and most are not systemic in the potato plant, a property of the at-plant neonicotinoid insecticides that growers value.
  7. Eliminating volunteers will reduce the number of CPBs that subsist on untreated potato plants and move into the crop when they run out of food. Neonicotinoid activity in the treated crop might have run out by this time, and hungry adult beetles can cause severe defoliation.
  8. By all accounts, this will be the more expensive year to grow potatoes. Be vigilant. Effective CPB control is required to maintain sustainable potato production.

Related Articles

Top Contenders for Potato Pests and Diseases Across Canada for 2022

Stacked Potato Plants Show CPB Resistance

Spud Smart’s 10 Most Innovative Products — Vayego

Trending This Week

Cover crop of rye and peas

Improving Our Soil Health for the Future

At our family farm, Swansfleet, in Bruxelles, Man. quality has always been the driving force behind everything we do. Lately, that drive for quality...
Potatoes in storage

Ultra-early Sprouting is a Storage Nightmare

For the last month, I’ve been receiving calls from growers scrambling with piles that are already sprouting. I’m not talking about one or two...
Female farmer

Number of Canadian Female Farmers Up by 12.3 Per cent

As of 2021 there are 79,795 female farm operators reported in Canada, up 2.3 per cent from 2016, newly released data from the 2021 Census...
Alberta Potato Conference and Tradeshow stage

Potato Growers of Alberta Wraps Up First Post Pandemic Conference

The Alberta Potato Conference and Tradeshow wrapped up its first event in three years on Nov. 17, 2022. The last day of the conference...

U.S. Harvested Potato Acres Down Three Per Cent

Potato growers in the United States are expected to harvest 906,000 acres of potatoes this year, the November 2022 crop production report from the...