Evaluation of flea beetle phenology and damage to carrot production

An unknown injury to carrots has been observed in California for several years. It has been identified as being caused by the larvae of a flea beetle (Systena blanda and Epitrix cucumeris). A study was conducted in 2013 to determine how prevalent the damage caused by flea beetles were to carrots grown in California and to how to best monitor their populations in the field. Flea beetle injury was determined to be caused by two species of flea beetles; palestriped flea beetle (Systena blanda) and the potato flea beetle (Epitrix cucumeris). Potato flea beetles were found to be best monitored by yellow sticky traps placed 1 meter above the plant canopy while palestriped flea beetles were best monitored by the use of a sweep net. We found a correlation between flea beetle populations and the amount of carrot injury seen at harvest.