Ladybugs are one of the most common and easily recognized members of a landscape. There are thousands of species of these beetles worldwide, with more than 400 that we know of taking up residence in the states.
The colorations of ladybugs can be extremely varied, and usually consist of reds, yellows, oranges or pinks. Some ladybugs have spots, some prefer stripes, and some don’t have any additional markings at all
These bright shells are a warning coloration that advertise the beetle’s bitter taste to hopefully discourage hungry birds, frogs, wasps and other predators from taking a bite. As added protection, many ladybugs can also secrete foul-tasting and sometimes poisonous secretions from their exoskeletons.
From a pest control perspective, ladybugs are some of the gardener’s best friends, as they eat a wide variety of plant grazers and sap suckers in both their adult and larval forms. While the diet of some ladybugs is specialized, many eat a wide variety of foods including aphids, scale insects, mealybugs and the eggs of pest insects such as Colorado potato beetles and European corn borers.
It is estimated that each ladybug consumes thousands of insects in its lifetime. Even in their young and growing forms they can eat around 25 insects a day. Their success in hunting and consuming plant pests has led to several exotic ladybug species being introduced into the states, with sometimes unexpected results.
Because of their innate hardiness and voracious appetites, ladybugs were some of the first insects to be widely used in the biological control of agricultural pests.
Australian ladybugs helped the U.S. orange industry fight off disaster in the early 1900s, while the commonly seen European seven-spotted ladybug found its way across the ocean years later and has established itself in landscapes throughout the country.
Many of the introduced ladybug species seem to co-exist rather well with native ladybugs, however there is a certain species among them that is not such a friendly neighbor. Hidden among our backyard beetles is a monstrous intruder, a ladybug that dwarfs our native species in both size and appetite.
Originally hailing from eastern Asia, the Asian lady beetle has established a strong population in the United States and Europe. Scientists believe the spread was started by shipping containers laden with hitchhiking adults over the last hundred years or so. Asian lady beetles didn’t lose their stowaway tendencies when they arrived, however, and these are the only ladybugs that prefer taking up residence in houses to escape the cold of winter. If you find congregations of ladybugs inside during the fall, winter or spring, chances are you have your very own local population of these tenacious beetles. Vacuum them up rather than giving them the boot, as Asian lady beetles produce a stinky and irritating liquid when squished.
Asian lady beetles do a very good job at eating a wide variety of insects deemed crop pests, and they are also remarkably resistant to pesticides. While this makes them ideal for an agricultural setting, studies are showing that these beetles are also disrupting native ladybug species. Asian lady beetles appear to harbor huge amounts of certain parasites that can be dangerous to native species, and they also feast on the eggs and young of native ladybugs whenever they can.
Rather than attempting to wipe out these introduced species, I recommend keeping native ladybugs in mind as you tend to the garden this year in order to give the species in your area the best chance of survival.
Stop using pesticides, and instead leave small populations of pests such as aphids and mealybugs alone. Left long enough, these will most likely end up attracting pest control more effective than chemical applications.
Brannen Basham and his wife, Jill Jacobs, operate Spriggly’s Beescaping, a business dedicated to the preservation of pollinators. Contact him at firstname.lastname@example.org.
Bee School set for March 30
The Jackson County Beekeepers will offer Bee School from 8:30 a.m.-4:30 p.m. Saturday, March 30.
The class will be at the Jackson County Extension Office at 876 Skyland Drive, Suite 6. It will include all information needed to start beekeeping.
The class costs $40 per individual and $50 per couple, and includes instruction, book, lunch, the beekeeping exam and a one-year membership to the Jackson County Beekeepers.
Registration is required at jcbeeschool.rsvpify.com.
For more information, contact the Extension Office at 586-4009 or email Christine_bredenkamp@ncsu.edu.