How to Tell the Difference Between Good Ladybugs and Bad Ladybugs
They look similar, but one type helps control unwanted insects in the garden while the other is a pest itself. Here's how to tell these look-alike bugs apart.
Finding a ladybug in your garden is usually something you want to see. These beetles are beneficial to your garden because they eat plant pests such as aphids and scale insects. However, multicolored Asian lady beetles look very similar to ladybugs, but have become a pest themselves. In the fall, it has become increasingly common to spot Asian lady beetles congregating in huge numbers on houses and other buildings. The beetles like to infiltrate homes for the colder months, can bite, and will release an unpleasant odor similar to stink bugs when disturbed. These invasive insects also have been pushing out native ladybugs. If you can tell the difference between the two insects, you might be able to stop an annoying problem before it starts.
Asian Lady Beetles Vs. Ladybugs
You can identify a ladybug by its markings and size. There are several different species, with most sporting red shells and various numbers of black spots. Their heads tend to be black with small white "cheeks." Ladybugs are typically rounder and smaller than Asian lady beetles if you look at them side-by-side. Asian lady beetles also have larger white "cheek" markings and have more white on their heads overall.
A sure way to tell the difference between an Asian lady beetle and a ladybug is look at the spot where the head meets the wings. If the bug in question has a black 'M' marking in that spot, that's a telltale sign you're dealing with an invasive species. Asian lady beetle shell color can range from light orange to bright red, so most will have a similar color to a ladybug.
Asian lady beetles are known to sneak into your home through cracks or holes when it gets cold outside, which ladybugs won't do. Light attracts the pests so they'll often congregate on siding on the south side of building, around door frames, and in windows. They may bite by scraping the skin they land on, which feels like a pinprick but won't cause any real damage. When threatened, Asian lady beetles release a stinky yellow that can stain surfaces and trigger allergic reactions.
While it's very rare, Asian lady beetles can infest dogs' mouths. If a dog happens to snap up some beetles, the insects may attach themselves to the roof of your pet's mouth. This won't always mean a trip to the emergency vet, though the beetles will usually need to be pried off. If swallowed, the insects can irritate a dog's gastrointestinal tract and in extreme cases, can be fatal, so make sure to keep your pets away from Asian lady beetles and check their mouths periodically.
How to Control Asian Lady Beetles
The best way to keep Asian lady beetles out of your home is by sealing and patching potential entrance points. Close up any gaps around windows, doors, and siding to minimize risk. The good news is that if they do get into your home, Asian lady beetles won't reproduce indoors and will make their exit in spring.
To get rid of Asian lady beetles in your home, your best bet is to vacuum them up and empty the vacuum when you're done. Contain them in a sealed bag before tossing into the trash so they can't crawl out. Avoid using pesticides because, in addition to exposing yourself to toxic chemicals, large numbers of dead beetles in your walls may attract other pests. Sticky glue traps kept out of reach of small children and pets are a safe option for smaller infestations.
Outdoors, you can clear them off the areas the beetles usually congregate with a broom or strong spray of water from a power washer or hose. Then scrub down the area with soapy water; the pests most likely won't return because the soap smell overpowers the pheromones that attract more beetles to the location.