The chemicals sprayed by low-flying airplanes on Tuesday are harmless to people, officials said Tuesday.
Parts of Oak Forest were doused with two chemicals, a pheromone that disrupts moth making and a pesticide called Bacillus thuringiensis var. kurstaki in an effort to battle the European Gypsy Moth.
Btk, as the pesticide is commonly called, is actually a naturally occurring biological material. The material doesn’t actually kill fully grown moths. Caterpillars who eat the substance die after about a week.
“When the eggs hatch, they feed on this substance … and that kills them,” said Greg Stack, a horticulturist with the University of Illinois.
Human and animals aren't affected by the chemicals.
"It’s safe to use. It only works against caterpillars because (they) have the right type of gut," Stack said.
The "right type" is an alkaline stomach, with caterpillars have and people don't.
A number of residents called Oak Forest police and the offices on Tuesday about the low-flying planes.
Airplanes targeted only for wooded areas with the spray. A certified aerial application contractor conducted the spraying, according to an Illinois Department of Agriculture letter sent to the city. The IDOA and the Slow the Spread Foundation have teamed with the United States Department of Agriculture and the United States Forest Service spray for the moth.
The IDOA had published a notice of a public meeting about the spraying in the local papers, city officials said. They also sprayed for the moths several years ago.
Gypsy moths aren’t native to Illinois or North America, according to the Illinois Department of Agriculture website. A French scientist studying silk moths brought gypsy moths to the United States in the late 1800s.
Mature moth caterpillars pupate from about the middle of June through early July in this state.