|© Robin Brickman|
Ladybugs are not bugs at all but rather beetles. We will call them lady beetles from now on. Their common names are ladybug, lady beetle and ladybird beetles. They received their name in Medieval Europe, where ladybugs moved in to remove insect pests from grapevines. They were dedicated to honor “Our Lady,” or “Bird of Our Lady.” (We have read it both ways.) From this the common name appeared.
These aphid lions will eat aphids, mites, small insects and insect eggs. They also dine with relish on, mealybugs, scale, thrips and other soft-bodied insects. With these beneficials you get a double bang for the buck. The larva, as well as the adult, will eat the above mentioned pest insects. The convergent lady beetle will eat 100 aphids per day for every day they can find them. The larvae of the convergent will eat 100 aphids per hour because they are growing youngsters.
DESCRIPTION OF LADY BEETLES
There are more than 400 different species of lady beetles in North America alone. Some, such as the convergent lady beetle are generalists and will eat a complete menu of pests. Others are specialists such as the two-spotted lady beetle which eats aphids, but mainly in trees.
Before you squash any “bug” in your garden or flower beds, read this. Lady beetles come in different sizes and colors. Some are black with no spots; others are gray with black spots. Some are red-orange with two spots or no spots. Some are striped and others are more yellow than red-orange. Some have blotches rather than dots on their back. They all have one pair of legs pointing forward and two pairs pointing back. Their length is from on-tenth of an inch long to one-fifth of an inch long.
Two consistent characteristics are: the larvae is alligator-like and all have the three pairs of legs. The larvae is either gray or black with yellow or orange bands or spots. The egg clusters are cream, yellow or orange and all are spindle-shaped.
The females lay 200 to 1,000 eggs over a two month period in the spring or early summer. The eggs are usually deposited close to their prey such as aphids, on protected leaves or stems.
Don’t confuse the “Mexican bean beetle” with the lady beetle. The Mexican variety belongs to the same family but eats bean plant leaves, rather than pest insects. Learn to tell the difference if you are planting beans.
WHERE DO YOU FIND LADY BEETLES?
Lady beetles will winter-over in mulch, under boards and bark, and in yard waste. They will use cracks in stone walls and openings between rocks in the wild.Lady beetles will emerge in the spring a week or two after the aphids emerge. You can find lady beetles where you find aphids; on the undersides of leaves, on stems near leaf joints, and particularly on new growth of a plant. It is more difficult to spot the eggs and the larvae of the lady beetle.
HOW TO ATTRACT AND KEEP LADY BEETLES
The best way to attract and keep all beneficial insects, as well as lady beetles, is to have a variety of plants in your yard, trees, shrubs, and different kinds of flowers. Each one will attract a different beneficial insect because each insect has different needs when they are not feeding on pest insects.
Lady beetles like pollen and nectar from flowers such as angelica, alfalfa, coffeeberry, Mexican tea, evergreen euonymus, oleander, morning-glory, goldenrod, dill and fennel and/or grains like buckwheat. They feed on dandelion, Queen Ann’s lace and yarrow so leave some in your yard or plant at the edge of your garden. You can buy a wildflower seed mix called “Border Patrol” designed to attract a number of the more common beneficial insects including lady beetles. Tansy will attract many lady beetles because tansy attracts a food source called tansy aphids.
Lady beetles will also eat “artificial foods” such as Bug Chow®, BugPro® or Wheast®. When the pest insect colonies are small, they will revert to other food sources so beetles will eat pollen, nectar and artificial foods.
AVOID BROAD SPECTRUM INSECTICIDES - In our files dealing with pest insects such as aphids, you can note that we recommend insecticides such as insecticidal soap or light horticultural oil as the line of first offense; those insecticides do not harm lady beetles. If the aphid problem is very serious, then we recommend using a pyrethrin product which will control the aphids but will also kill any lady beetles as well. That is why we always recommend using any insecticide with care and only on plants with a serious problem.
BUYING LADY BEETLES
If you are overrun with aphids and have not seen lady beetles in your yard, it is possible to buy them. Before you do, please read the following.
Most of the “lady beetles” purchased for release in home landscapes come from California. These beetles are taken from the Sierra Mountains by the hundreds of thousands. When their winter period is over, they fly up to one mile high and are caught on the winds sweeping towards the valleys where aphids are located. They must fly to burn off the remaining fat accumulated in the previous year before they can feed in the spring.
If you purchase the same convergent lady beetles, they are likely to fly off before they can do any good for your property. To help the successful release of these beetles, release them only in the late evening. Before the release, water the area with a hose so water is available to them. To further insure some hang around, find a plant which has aphids. Place garden fleece over the plant and place the lady beetles under the fleece. Some of them will fly against the fleece and fall on to the plants with the aphids. Perhaps they will stay to eat the aphids and hang around for the year.
Before a female can lay eggs, she must feed upon aphids. If you are buying lady beetles, try to keep them long enough for them to lay eggs. This will ensure a current year crop of adults and even those adults will lay additional eggs.
Before you buy lady beetles, read our section on “green lacewings”. These insect are also called “aphid lions” and may be easier to release. The combination of these two beneficial insects is gang busters against aphids.
SWARMING LADY BEETLES
Since 1991 the incidence of lady beetles swarming on houses and buildings in yardeners’ yards has been increasing. In one respect this is good because the use of broad spectrum pesticides was reduced, permitting more of these insects to live. The bad feature happens when your house has been selected.
It is important to know that these are not our own native lady beetles. They are imported lady beetles from Southeast Asia. They function in your landscape during the growing season just as well as our own natives, but in the winter they do not migrate. They look for a protected place in which to spend the winter and your house may well be their choice. It is a characteristic of these beetles to congregate in the fall when colder weather approaches. They are trying to escape the bad weather. The reason they are attracted to your home probably results from heat coming from the house, the color of your home or it’s orientation to the rays of the sun.
Unlike the native lady bug, these Asian beetles will bite if offended. The bite is not dangerous not terribly painful, but it is still a bite.
There are four solutions to your lady bug invasion problem.
1. The Most Work - Caulk around windows and doors and along the bottom of the facia boards. Be certain the soffet vents and other ventilation openings are screened properly. Remember if lady beetles are entering your home so is cold winter weather and the heat of summer.
2. Use a vacuum cleaner to suck them from the inside and any areas on the outside where they bother you. Take the bag away from the house and empty it in some other area. The lady beetles will live through the ordeal. Just don’t become hysterical over their gathering!
3. The third solution is one we do not recommend and that is the application of an insecticide to kill these beneficial beetles. Insecticides do not work well in colder weather and our object is to keep them alive so they can continue their aphid-eating qualities next year.
4. The easiest solution is to live with the problem. Generally these insects will disappear into the woodwork for the winter and not be seen much until spring returns. They don’t do any serious damage, though they can clog up light fixtures from time to time.