Eliminating shotgun holes in nursery stock

Red headed flea beetles (Systena frontalis) are sneaky. They overwinter in the root zone, leading to a false sense of complacency for nursery growers until June. That’s when adults emerge and create the classic shotgun holes on ornamental crops, ruining their retail value.

Past recommendations have been pesticide spray treatments once the adults emerge in May and June. By waiting, growers have missed the perfect opportunity to kill adults before they emerge in the spring. Eliminating the larvae before they pupate means zero adults emerging.

Koppert at Ocean Spray

An excellent example is Koppert’s success in eliminating the pest from Ocean Spray’s cranberry fields. Researchers at the firm ran multi-year trials in cranberry beds after growers anticipated losing a key chemical pesticide. They found that Capsanem was highly effective at controlling the red headed flea beetle (RHFB), consistently working when applied correctly.

Their most striking finding? Sites treated in 2023 required no additional treatment in 2024, indicating long-lasting population suppression.

Use Capsanem to control RHFB larvae

The takeaway: apply Capsanem to effectively impact RHFB larvae. They weather the winter as eggs and hatch into the larval stage at approximately 250 growing degree days (GDD). This makes early to mid-April the perfect time to target applications for most growers. Those larvae are sitting ducks when entomopathogenic nematodes are released into their workspace. A well-timed and executed Capsanem nematode drench treatment in late March or early April will execute nearly 100% of the year’s RHFB larvae population.

Application timing is especially critical with RHFBs. Soil warmth activates the larvae, leaving a short window of opportunity. Problems like poor shipping, clogged equipment and incorrect dosing interfere with the efficacy of treatment, so attention to detail is important.

One and done

One well-timed, well-done application of nematodes applied with a non-ionic surfactant eliminates 99% of the need for pesticide sprays against these pests during the summer. You’ll also have zero negative impact on native beneficial insects, who’ll thank you for allowing them to continue working throughout the summer growing season.

Research now clearly shows that Capsanem nematodes effectively control red headed flea beetle larvae and can suppress populations for multiple years when applied correctly. Ready to set up a plan? Reach out to the nematode experts at Koppert and let’s dial in the details. We know nematodes!

For more: bit.ly/rhfb-gone