Meet the Gardener’s Friend – The Ladybird
This tiny, colorful insect is called a ladybird. In North America it is known as a ladybug or a lady beetle. Other countries have their own names for it. Although beetles are not everyone’s favorite insect, ladybirds are generally viewed with fondness. They fascinate children, and gardeners and farmers welcome them with open arms. What makes them so popular?
Most species of this friendly little beetle just love to eat aphids, the tiny soft-bodied insects that suck the life out of garden and agricultural crops. Some adult ladybirds can consume several thousand aphids in their lifetime-and the ladybirds’ larvas have huge appetites too. In addition, the beetle feeds on many other insect pests, and some already relish plant-damaging mildews. No surprise gardeners and farmers welcome the ladybird!
In the late 1800’s, cottony-cushion extent insects were accidentally imported from Australia into California, U.S.A. The pest multiplied so rapidly that it threatened to wipe out the citrus orchards and destroy the industry. Knowing that in its home country this extent insect posed no threat to crops, an entomologist went to Australia in search of the insect’s natural enemy. He found it to be the vedalia, a ladybird beetle. About 500 of the beetles were shipped to California, and within a year the extent was virtually wiped out. The citrus orchards were saved.
A Year in the Life of a Ladybird
This attractive little beetle has a round or oval, dome-shaped body and a flat underside. Despite having voracious appetites, most species of ladybirds are under a half inch [12 mm] in length. Hard, shiny wing covers called elytra protect the delicate flight wings underneath and give the beetle its colorful pattern. When the insect flies, the elytra open up and lift out of the way. Although ladybirds are often portrayed as red with black spots, the approximately 5,000 species truly have a variety of color and identify combinations. Some are orange or yellow with black spots. Others are black with red spots. A few have no spots. nevertheless others have checkerboard markings or stripes.
Many species live for a year. During winter, adults hibernate in a dry, protected location. Awakening when the days get warmer, they fly in search of plants infested with aphids. The female, after mating, lays a cluster of tiny yellow eggs on the underside of a leaf near a good aphid supply. Each egg hatches into a six-legged larva that looks more like a ferocious little alligator than a future ladybird. Since the larva spends its time eating aphids, it soon grows too big for its skin. After shedding its skin several times, it attaches itself to a plant and produces a pupal skin. Inside the pupa, the larva continues to grow until it finally pops out as an adult. At first soft and pale, it remains on the plant while its body hardens. In a day, its distinctive markings appear.
Enemies learn to avoid the colorful ladybird. When threatened, the beetle squirts a yellow, foul-smelling, horrible-tasting liquid from its joints. Predators, such as birds or spiders, never forget their first unpleasant encounter, and the insect’s bright color serves as a continued reminder.
A Problem Ladybird
One species of ladybird, initially used as pest control, is proving slightly of a pest itself. The harlequin ladybird, also called the multicolored Asian lady beetle, lives happily with other species of ladybirds in its native habitat in northeastern Asia. Because of its exceptional appetite for aphids and other plant pests, it was recently introduced into North America and Europe. Unfortunately, it has abundant native ladybirds by eating all their food. More than that, when its preferred diet runs out-and without its natural enemies to control it-the hungry beetle turns to devouring local ladybirds and other advantageous insects. Entomologists view the future with alarm as they foresee the extinction of some ladybird species. The harlequin also makes itself unpopular by gorging on mature fruit ready for harvesting and by invading houses in enormous numbers in the autumn to escape the winter cold.
A few other species of ladybirds eat precious crops instead of insect pests. Happily, however, the great majority are a gardener’s delight.
Welcome the Ladybird
How can you attract ladybirds to your garden? Native flowering plants provide a welcome source of pollen and nectar. A patch of weeds and a shallow dish of water will encourage them too. If possible, avoid using chemical pesticides. Some dead leaves left on plants or on the ground during the winter will provide cozy hibernation sites. Try not to squash any bugs and eggs you find in your garden. You could be killing the next generation of ladybirds.
Remember, just a few of these attractive little insects will help you keep garden pests under control without the use of unhealthy pesticides. If you look after ladybirds, they will reward you for your care.