The name flea beetle describes many species of small beetles that chew tiny shot-holes in plant foliage and jump around like fleas when disturbed. Although some species feed on a wide range of plants, most FB species attack a single species or family of related plants.
New Hampshire garden crops most likely to suffer early-season FB attack include cabbage-family crops, potatoes, tomatoes, eggplant, beets, corn, grapes and spinach.
FB damage is worst in spring. Heavy infestations can kill an entire planting of newly-germinated seedlings or severely weaken young transplants. FB damage also renders plants vulnerable to attack by pathogens; in some cases, the beetles actually transmit disease such as early blight of potatoes. Larvae of most FB species feed on the roots of the same plants being attacked from above by adults. Other FB larvae mine leaves or feed on underground stems.
Adult FB are small, elongate-oval beetles, typically between 1/16” (potato FB) and 1/5” (grape FB) long, with narrow prothorax and head. Most species are black, brown or another dark color; some with striped wing covers.
Prevention and non-chemical control
Since adult FB feed on weeds in the early spring and late fall and FB larvae may be present in large numbers on weed roots, controlling weeds in and around the garden will go a long way towards controlling this pest. Providing the gardener has paid rigorous attention to crop rotation and fall garden cleanup (depriving adult FB of overwintering habitat in the garden), floating row covers will offer excellent protection for direct-seeded crops and new transplants.
Feel free to continue the conversation and add your own discoveries on pest control by leaving a comment. If you have had great success with a particular organic method, let us know what worked for you! Thanks!
ACKNOWLEDGMENTS: The information above was gleaned from the UNH Cooperative Extension Website a GREAT resource!