Flea beetle is a term used to describe a type of small beetle that is often referred to as a garden pest. Unlike other species in the leaf beetle family, they are jumpers, moving from plant to plant, chewing small holes. A swarm of flea beetles can cause extensive damage to certain vegetable crops, especially new plants.
Adult flea beetles often burrow into the soil in the spring. After the temperature is right, they will show up and feed. A short time later, the female beetles will lay eggs near the bottom of plants. Usually, the larvae that appear do not do much harm. An exception to this rule is tuber flea beetle, which larvae chew on the roots of many underground vegetables, especially potatoes.
Compared to many other types of beetles, adult flea beetles are quite small. Many times, most species will not grow to be longer than 1/8 inch (3.17 millimeters) long. While some of them are a plain black or brown, some have a pattern or back that strips. Some can also be an attractive sparkly, metallic blue, silver or green hue. Their large hind legs enable them to jump great distances, similar to a flea.
Flea beetles are not always considered to be garden pests, as sometimes they will consume weeds or other unwanted plants. Many species of flea beetles usually have a preference for certain types of plants, especially vegetable plants. Cabbage flea beetle, which supplies primarily on cabbage plants, is a good example of this. Many times, only the adult beetle is responsible for plant damage.
Evidence of flea beetles can often be seen clearly on plants. These beetles will chew small holes in the leaves. This is sometimes referred to as shot holing, as the damage is strongly reminiscent of shotgun damage from a shotgun.
Although a severe flea beetle attack can cause older plants to wilt or die, younger newly established plants that are most prone to flea beetle damage. Crops grown for their leaves, such as lettuce or cabbage, can initially become worthless after a flea beetle attack.
Farmers and gardeners can prevent extensive damage from flea beetles by closely monitoring their plants every day. Some visible beetles should be removed. If more than a few beetles are found on each plant, other methods of getting rid of flea beetles should be considered.
Trap crops are a way to control a flea beetle attack. Planting a crop that is attractive to these beetles, such as radishes, can sometimes cause flea beetles to feed on these instead of the main crop. A trap crop is usually planted some distance away from the regular crop to lure beetles away. If the trap crop method does not work, pesticides may be needed.