Harmful Soil Insects And Other Pests
PESTS CONTROLLED IN THE SOIL
Ants: Treatment of soil with chlordane disposes of many ant species annoying in the garden. Soil under peonies especially should receive this attention to kill ants that take honeydew from the buds. If ant nests can be located, dusting or spraying with chlordane will mean much better control, as this destroys young ants which might otherwise not be reached. When ants march in from surrounding woods or from other properties, use sweetened ant poisons or prepared baits.

White Grubs: Many species invade gardens and lawns. Larvae or grubs of the May beetle or June bug are particularly destructive.

The grubs spend parts of three years underground. Eggs are de­posited in June and hatch a month later into larvae that feed on decaying vegetable matter and on roots of plants. They continue feeding through a second year, during which they do severe damage to lawns. Early in spring of their third year, they stop feeding and turn into adult beetles, emerging to begin the life cycle over again.

Application of chlordane or calcium arsenate will destroy the first and second broods of grubs, but may not show much effect on the brood that is about to emerge as adult beetles in May and June. This misleads those who have used chlordane; they think it is of no value. However, for at least four years following date of treatment, no living grubs will be found, once the spring brood has emerged.

In lawns, grub injury may be limited (a paler green color in patches may indicate loss of roots and poor nutrition due to feeding of second-year brood), or may be severe. When severe, the roots often are cut off just below the surface so sod can be rolled back like a carpet, exposing feeding grubs underneath. In less severe cases, removing a square foot or two of light, weak sod and digging into the soil should be enough to reveal whether the dirty-white curled larvae with blackish heads are present.

Japanese Beetle: These differ from June bugs in their life cycle, but, like them, do severe damage by eating at plant roots when underground. Japanese beetle grubs spend 10 months in larvae form, surviving one winter. In late May or early June the grubs stop feeding and pupate, emerging as adult beetles. They live for little over a month, feeding on leaves and flowers and laying eggs, usually selecting lawns or other grass areas for the latter purpose. Late-hatched adults may survive as late as early October.

Although these beetles are voracious eaters of prized flowers and foliage, we are concerned with the underground, root-eating period of their life cycle, which begins when the young hatch from eggs during late summer.


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