You only have to worry about orange dog caterpillars in the larval stage.
Only in pest control will you find the following three words strung together: orange dog caterpillar. Although the orange dog caterpillar (Papilio cresphontes Crame) might serve as one of mother nature’s grand irony’s, for it morphs into the beautiful swallow tail butterfly upon maturity, it’s no understatement to say this citrus-sucking, leaf-chewing pest has an appearance just as hideous as its name implies. With dirty-white mottled blotches that resemble bird droppings dripping off its light-brown body, the orange dog favors citrus trees, especially small specimens, and makes short work of their foliage. You can kill orange dog caterpillars the old-fashioned way, by crushing them, or by using a naturally occurring bacteria, such as bacillus thuringiensis.
Pull a suspect caterpillar from the tree and examine it to confirm you have an orange dog infestation. Orange dog caterpillars measure between 1-1/2 and 2 inches long, have light-grey to dark-brown bodies covered with creamy white mottled markings, and extrude their osmeterium gland, which resembles a forked snake’s tongue, when threatened. The osmeterium gland releases a rancid-butter odor when it emerges.
Pull orange dog caterpillars from small trees and place them in a plastic bag. Throw the bag of caterpillars in the trash bin or give it to your sanitation service on ecological waste pickup day. You also can throw the orange dog caterpillars on the ground and step on them, or place them in a container of rubbing alcohol to kill them.
Scrape the orange dog caterpillar egg sacs from the trees into a container of soapy water using a garden knife. Toss the egg sacs down the drain or onto bare ground.
Combine 4 teaspoons of a pesticide containing 15 percent bacillus thuringiensis as its active ingredient with 1 gallon of water in a tank sprayer if you have a major orange dog infestation. Spray the tree’s foliage until running off. Repeat the foliar application every two weeks if needed.
Mix together 3 tablespoons, or 1 1/2 ounces, of an insecticide containing 22.5 percent carbaryl with 1 gallon of water in a tank sprayer if bacillus thuringiensis proves ineffective. Spray the foliage from 1 foot away until covered on all sides. Wait at least five days before harvesting any fruit from the treated tree.
Spray insecticides on a non-windy, dry day.
Always wear protective glasses, chemical-proof gloves, long sleeves and long pants when working with insecticides.
Andrews, A.J.. "How to Get Rid of an Orange Dog Caterpillar." Home Guides | SF Gate, http://homeguides.sfgate.com/rid-orange-dog-caterpillar-73235.html. Accessed 25 April 2019.
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