By Kat Yares, Garden Guides Contributor
About Cucumber Beetles
The cucumber beetle is just one of several varieties of leaf eaters
of the insect genus Diabrotica. Most common are the spotted and
striped beetles, identified by the yellow stripes and black spots
on the beetle bodies. The spotted cucumber beetle resembles in
shape the ladybug but, unlike the ladybug, is not beneficial to the
garden.
The larvae are laid in eggs on the underside of the leaves of the
affected plants. After hatching, they bore underground and attack
the roots of the plant.
Prevention and Control
Pyrethrum containing insecticides are the most used way of
controlling the cucumber insect beetles. To prevent future
re-infestations, the plants and debris should be removed from the
area. The ground around remaining plants should be free of litter
and cultivated regularly to remove hiding places for the beetle and
the larvae.
Affected Plants
Cucumbers, squashes, pumpkins and melons.
Damage
Adult cucumber beetles attack the leaves and stems of young plants
and later attack the buds and fruits of the mature plants. As
larvae, the cucumber beetles attack the roots and stems beneath the
soil causing the plant to die. Cucumber beetle larvae are often
called corn rootworms and can decimate a young corn crop.
Predator Insects
Soldier beetles, parasitic nematodes, Braconid wasps and Tachnid
flies will prey on the adult cucumber beetle. The eggs fall prey to
lacewings and ladybugs.
Natural Insecticides
A mix of 1 cup wood ash, 1 cup hydrated lime and 2 gallons of water
can be used as a spray for the cucumber beetle. Spray both sides of
the plant leaves thoroughly.
Other Methods of Control
* Mulch heavily around plants that cucumber beetles favor. Adult
beetles have difficulty moving from one plant to another over
mulch.
* Plant radishes, nasturtiums and odiferous marigolds as a border
around cucumber beds or circling squash, melon and pumpkin
hills.
* Planting castor beans among the plants also appears to repel the
cucumber beetle.
* Well-placed bat houses can help in the eradication of many
unwanted insect pests.
