Flea beetles hop and fly from plant to plant, chewing tiny holes in leaves as they go.
We are not talking about the blood-sucking, disease-carrying fleas on squirrels. Instead, flea beetles are plant pests. Generally, they do not cause a lot of damage. After all, each flea beetle is only 1/16 to 1/8 of an inch long. If enough of them show up, the damage can slow growth or provide points of entry for other problems. Let’s see what your plants are facing.
Flea beetle varieties
There are dozens of leaf beetle species. Here are just a few:
• Black flea beetle (Phyllotreta pusilla) - dark olive green or shiny black
• Palestriped flea beetle (Systena blanda) - broad white stripe down each wing
• Potato beetle (Epitrix subcrinita) - shiny black or bronze
• Striped flea beetle (Phyllotreta ramosa) - black with curved yellow or white stripes
• Tobacco flea beetle (Epitrix hirtipennis) - brown with black markings
Flea beetle host plants
Flea beetles feed on many families of edible garden plants:
Also, carrots, corn, and sweet potatoes may be on the menu. Flea beetles are also attracted to yarrow, but this is good. Yarrow acts as an insectary. Beneficial insects have evolved to lay their eggs in plants such as yarrow, knowing that flea beetles and other pests will provide their young with an easy first meal. Other beneficials, such as big-eyed bugs, will also feed on flea beetles, so go easy on the pesticides. Pesticides don’t work very well on flea beetles anyway. They hop or fly away and feed on neighboring plants.
Flea beetle damage
Pitting and small, irregular holes in leaves may merge to create raggedy areas. The holes are smaller than the damage caused by shot hole disease. Shot hole disease holes usually begin as 1/10 to 1/4 inch diameter red or purplish spots.
Flea beetle feeding holes may have a pale green or yellow ring. Those spots will dry up. The dead tissue then dries up and falls away, leaving a shotgun blast appearance. Small, irregular leaf holes may also be caused by springtails, though it is more likely to be flea beetles. Flea beetles may also damage fruits and root systems.
Flea beetle lifecycle
Flea beetles lay tiny eggs in weeds, plant debris, and the soil surrounding their favorite food plants. After the eggs hatch into thin, white larvae, feeding may begin above or below ground. After a month or so, larvae pupate in the soil. When they emerge as adults, they use their big jumping legs and wings to go wherever they want to feed.
Flea beetle control
Pesticides are not very effective on flea beetles. In most cases, control isn’t necessary. If an infestation starts to cause serious damage, use basic sanitation in the garden. Removing all those tiny hiding places can make life difficult for flea beetles. Reflective mulch and white sticky traps can also be used to manage flea beetles. Row covers may block pests from reaching plants in the first place. Once they are present, you can lightly sprinkle the area with diatomaceous earth (DE). Flea beetles don’t care too much for sulfur, either.
Some commercial growers vacuum off heavy flea beetle infestations, but I don’t recommend it for the home gardener. Your vacuum cleaner would never be the same!
You can grow a surprising amount of food in your own yard. Ask me how!
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