Fall and early winter are excellent times to prevent insect problems that occur next year. I received a few reports of “worms” or grubs now feeding on the roots of plants. The most common are “white grubs” feeding on a variety of different plant roots tasty to them.
|White grubs removed from the soil where they feed on plant roots|
These white grubs found now pupate, or change into adults, over the winter. The adults of these white grubs are sometimes referred to as “chafers” or in a much larger category of scarab beetles.
|Common midwestern June Beetle|
The most common one too many Midwesterners is the June beetle. To desert dwellers, like myself, who have lived here a long time might think of the metallic green June beetle that attacks soft fruit. But these pests come in a variety of colors, sizes and even racing stripes!
|Our common metallic june beetle that attacks soft fruit|
The easiest way to control these insects is to sprinkle granular insecticides that are specifically labeled for “grubs” or insects feeding on the roots of plants. Follow the label directions but normally the insecticide impregnated on the granules is washed into the soil with a light application of water after they are applied. If you can’t find granules, then use a liquid applied to the soil as a drench that protects the roots.
|Ten-lined june beetle that is an occasional pest in our desert|
For those of you who prefer an “organic” or more natural approach then look for beneficial nematodes or bacteria that can be applied to the soil around these plants. This approach gives a “slower kill” but can be just as effective as commercial insecticides over time with an added benefit that they persist in the soil for a much longer time.
The most common plant attacked and reported by many readers is Lantana. Evidently white grubs love the roots of these plants. It is a safe bet, if these plants were struggling this past summer, the roots were probably attacked by white grubs.