Beginner

Scientific Name
Epitrix cucumeris

Identification
Adults are black with brown legs, very small, about 1.7 mm long and 1 mm wide. Flea beetles do not fly, but jump very quickly when disturbed. Larvae are small, slender, and white with dark brown heads and minute legs. Full grown larvae measure 5 mm in length.

Flea beetle feeding damage has a shot-holed appearance.

Often Confused With
Red-headed flea beetle

Period of Activity
First generation: May-June

Second Generation: Late July

Scouting Notes
Scouting for flea beetles should start at crop emergence using the same 10 sampling sites you selected for CPB. Make observations as you approach the selected plants. Take care not to let your shadow fall on the plants you intend to examine so that the flea beetles will not jump away. Examine a 4th terminal leaflet on each plant you are examining. Report the number of flea beetles per plant/stem and the average number of shot holes per terminal leaflet examined.

Flea beetle numbers tend to be higher in rows close to field borders, especially in potato fields close to a cruciferous crop like canola, broccoli, mustard, cabbages etc. If this is the case, scout the border rows separately from the reminder of the field as suggested for Colorado potato beetles.

Thresholds
Average of 15 shot-holes per 4th terminal leaflet examined or 25 flea beetles per 50 plants.

Advanced

Scientific Name
Epitrix cucumeris

Identification
Adults are black with brown legs, very small, about 1.7 mm long and 1 mm wide. Flea beetles do not fly, but jump very quickly when disturbed. Larvae are small, slender, and white with dark brown heads and minute legs. Full grown larvae measure 5 mm in length.

Flea beetle feeding damage has a shot-holed appearance.

Often Confused With
Red-headed flea beetle

Biology
Life stages: eggs, larvae, pupae, adult beetles.

Flea beetles overwinter as adults in plant litter on the soil surface. In the spring, adults move to potato fields and feed on the developing foliage. Flea beetles chew small holes in leaves leaving a shot-hole appearance. Females lay eggs in the soil around potato plants. Eggs hatch in about a week into tiny larvae that feed primarily on the fine roots of potato plants. Occasionally, flea beetle larvae feed on tubers. This causes small, round, dark-brown lesions on tubers

After 4–5 weeks, the larvae reach maturity and pupate in the soil to become adults. This new generation of adults emerges from the soil, usually in late July, and feeds on potato leaves. Adults move to overwintering sites as day length and temperature decrease.

Usually 2 generations per season develop in Ontario. Flea beetle populations are higher when potatoes are grown close to crucifer crops.

Period of Activity
First generation: May-June

Second Generation: Late July

Scouting Notes
Scouting for flea beetles should start at crop emergence using the same 10 sampling sites you selected for CPB. Make observations as you approach the selected plants. Take care not to let your shadow fall on the plants you intend to examine so that the flea beetles will not jump away. Examine a 4th terminal leaflet on each plant you are examining. Report the number of flea beetles per plant/stem and the average number of shot holes per terminal leaflet examined.

Flea beetle numbers tend to be higher in rows close to field borders, especially in potato fields close to a cruciferous crop like canola, broccoli, mustard, cabbages etc. If this is the case, scout the border rows separately from the reminder of the field as suggested for Colorado potato beetles.

Thresholds
Average of 15 shot-holes per 4th terminal leaflet examined or 25 flea beetles per 50 plants.

Management Notes
Control of potato flea beetles is rarely needed because most of the crop protection materials used against CPB also control flea beetles.

Destroying weeds and crop residues adjacent to the field in the fall help to reduce the build-up of flea beetle populations.