Some lesser-known invasive bugs


Ken Johnson, U of I extension
| Dedicated to McDonough County Voice, USA TODAY NETWORK

JACKSONVILLE – When it comes to invasive insects, a lot of our attention is focused on those that cause great damage, such as: B. Japanese beetles and emerald green ash cutters. However, there are a few other invasive insects in Illinois that you should be aware of.

Asiatic tiger mosquito (Aedes albopictus)

Asian tiger mosquitoes get their name because of their white and black color pattern. Adults have black and white ribbons on their legs and a white stripe down the center of their head.

Asian tiger mosquitoes feed during the day. They are often found in shady areas where they rest on foliage near the ground. While they may not have particularly painful bites, they are persistent.

In addition to their pesky bites, these insects can carry and transmit Zika, dengue, or chikungunya viruses. However, they are nowhere near as effective carriers of these diseases as some other mosquito species and are not a problem in Illinois right now.

Women lay eggs on the sides of water containers like hoops, bird baths, and tree holes. The eggs hatch when covered in water, usually due to rain. The mosquitoes don’t fly very far. Hence, eliminating habitats for oviposition will go a long way in reducing populations. Covering your skin and using an insect repellent that contains DEET, picaridin, or lemongrass oil can help prevent bites from Asian tigers and other mosquitos.

Spotted wing Drosophila (Drosophila suzukii)

Spotted Wing Drosophila (SWD) was first found in the continental US in California in 2008. Since then, it has spread across the country, including Illinois. It was likely spread in infected fruits.

Most fruit flies lay their eggs in fruits that are already ripe or overripe. On the other hand, SWD lays its eggs in ripening fruits just before harvest. When the larvae hatch in the fruit, they begin to feed and the fruit begins to collapse in just two days.

SWD is primarily a pest of fruits such as strawberries, raspberries, and blueberries. They also attack fruits like cherries, peaches, grapes, and tomatoes. It will also feed on “alternative” hosts such as elderberry, pokeweed, and dogwood.

SWD are small (1/8 inch) flies with red eyes, a brown rib cage, and black stripes on the belly, like many other species of fruit flies. Male SWDs have a dark spot on their wings near the wing tip. Female SWD are a little harder to identify because they do not have wing spots. You have a fairly large, jagged ovipositor. These gears allow the females to lay eggs in unripe fruit.

Good sanitation is important when it comes to managing SWD. Do not leave damaged or overripe fruits in your garden. Instead, put the fruit in a clear bag and leave it in the sun to kill any flies that may be present. Insecticides can also be used to control populations. Read and follow all directions on the label.

Good Grow Tip of the Week: For more information on these and other invasive species in Illinois, visit the Good Grow Blog at