Adult chinch bugs are black with white wings folded over their backs and measure about 4mm long. Newly hatched chinch bugs or 'nymphs' are yellow upon hatching but soon turn red, with a light coloured band across their abdomens. With each molt, nymphs more closely resemble the adults.
Chinch bugs live in the thatch layer of a lawn where they feed on the grass by piercing the plant with their mouth and sucking the plant juices. When the chinch bugs feed, they release enzymes that facilitate easy feeding. The enzymes continue damaging the plant after feeding, and cause the grass to turn brown and potentially die.
Chinch bugs are generally found in hot sunny areas of a lawn. They tend to aggregate, which initially results in localized dead patches. These dead areas are brown, irregular sunken patches, which can coalesce into larger dead areas. Damage generally becomes evident in July and August when temperatures get hot and drought conditions become more prevalent.
Heavy infestations can be identified by simply parting the thatch and looking for the chinch bugs. Light infestation can be discovered by cutting the bottom from a large tin can and pushing the can into the lawn and filling it with soapy water. Any chinch bugs present will float to the surface.
The adult chinch bug spends the Winter congregated under trees and shrubs, as well as on the edges of lawns, under hedges and in flower beds. As the temperatures become warmer in Spring, the adults move into the lawn and begin depositing eggs. As many as 20 eggs per female may be laid during May and June. The eggs take about 20-30 days to hatch at temperatures below 21°C but can hatch in as little as a week when above 26°C.
The nymphs grow slowly at the beginning of the season because of cool temperatures but speed their development by July. Damage may be visible from late June through August. When cool temperatures arrive, the mature chinch bugs seek out protected areas to spend the Winter.Talk to your local Nutri-Lawn about assessing a potential chinch bug problem in your lawn.