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Beginner

Scientific Name
Systena frontalis

Identification
Adults are black, with a dark-red spot on the head, and approximately 4 mm long. They have large hind legs, allowing them to jump very quickly.

Often Confused With
Potato 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
Not established. It is a sporadic pest in Ontario.

Advanced

Scientific Name
Systena frontalis

Identification
Adults are black, with a dark-red spot on the head, and approximately 4 mm long. They have large hind legs, allowing them to jump very quickly.

Often Confused With
Potato flea beetle

Biology
Life stages: Eggs, larvae, pupae, adults.

Adults are occasionally found feeding on potato foliage and may also be found on a wide variety of plant species, including grapevine. Their peak numbers usually occur by the middle of August.

Adults chew holes in the leaves. Their abundance could depend on the proximity of corn fields and other sources of food.

Larvae may be found on the roots of a wide variety of weeds and cultivated plants, including corn.

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
Not established. It is a sporadic pest in Ontario.

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.