Never buy Lady Bugs!! Seriously.
For those of us who know ‘bugs’, and know biological pest control, there is one great reason for commercially available and lab-produced ladybugs: They are the “gateway bug.” An insect that people regularly see, generally like, and view as the poster-icon for beneficial insects. If shopping for “ladybugs” and even applying them to your garden means you stop spraying chemicals, then that is OK with us. (Just by stopping the spray, the better beneficials will show up and do what ladybugs won’t.)
The key to the above statement is ‘lab-produced.’ If you do not get properly reared insects then they are massively detrimental to the environment, our industry, and your garden.
Read on, and learn why the commercial trade of ladybugs should stop and why you should never buy ladybugs.
1. They are harvested from the wild in the US. Their numbers have been decimated and populations weakened which has allowed for competition from Asian Ladybug.
2. They bring with them ladybug parasites that are transferred to our local population.
3. They are collected during hibernation and refrigerated, but are migratory – which means they will eat a few aphids then go back to Colorado. The ones you release are not the ones you see in your garden (there are many native species).
4. The trade is by special permit to collect from the wild which has been being fought by environmental groups since the 60’s.
5. Ladybugs are known to eat aphids, but actually graze and are not as important for aphid controls as other predators (we just recognize them and see them because they are big and colourful.)
“Commercial insectaries distribute beetles that have been “harvested” from natural winter aggregation sites. If lady beetles are collected in this dormant state and transported for field release, even among aphid infestations, they usually migrate before feeding and laying eggs. This migratory behavior before feeding is obligatory. Releases of such “harvested” convergent lady beetles could be a waste of time, money, and beetles. Insectaries may feed the adult beetles a special diet after they have been collected to minimize their migratory behavior. Only such preconditioned beetles should be purchased. Additionally, these harvested beetles may be parasitized.”
(Cornell University: https://biocontrol.entomology.cornell.edu/predators/Hippodamia.php. )
6. Native, commercially available and sustainably produced beneficial insects are produced in Canada and the US for more effective aphid control.
7. Aphidoletes aphidimyza is the number one choice for commercial greenhouses and outdoor nurseries and landscape gardens. It is a midge, who’s larva can eat hundreds of aphids, and the adults lay hundreds of eggs – it just simply works. You can also buy the hoverfly “Eupeodes americanus,” (which is an important pollinator as an adult and it’s larva eats more aphids than any other) or brown lacewing “Micromus variegatus” which is nocturnal (so people don’t know it exists) and eats far more aphids than ladybugs.
8. They are produced in British Columbia and sold through Canadian and American Distributors. Just think: You can support local business while saving the environment!
Here is a link to distributors:
9. The international organization of biocontrol producers forbids the resale of wild-collected insects/mites.
“IOBC Global: The International Organization for Biological Control (IOBC) was established in 1956 to promote environmentally safe methods of pest and disease control in plant protection.” https://www.iobcnrs.org
10. I’m not making any of this up. Cornell University has done extensive work on this subject. They even have a project at lostladybug.org which is hoping to teach people to identify and protect the native ladybug species (which you don’t need to buy). They even marked commercially bought ladybugs and released them and some were found by entomologists at UofC Davis a short time after (across the continent).
11. For aphid control, native parasitic wasps called Aphidius will also volunteer in your yard if you don’t use chemicals and don’t spray with dish soap or something harmful like that. They look like bronze, swollen aphids. Chances are you have them, which means, chances are, aphid populations are on the decline anyways. And Aphidius are just the tip of the iceberg. You can expect all sorts of native beneficial insects to show up and eat your aphids if your garden is healthy, organic and not sprayed with any soap, detergent, acid, base, or chemical.
12. Plant a variety of plants. Let plants flower or grow them for their flowers. Consider leaving leaf-debris to provide over-wintering sites for native ladybugs when there is no risk of spreading plant disease.
13. Never use a home-made “bug spray” or a commercial chemical product. Even home remedies use a soap or detergent or acid. This strips the wax coating off the plants leaves, weakening them and making them more attractive to the next wave of pests. In the meantime you have also killed the predators – which can detect soap residues or see the plant stress as it reflects a different wavelength, and the predators will not return.
14. Lastly, ladybugs are simply not the best predator of aphids. You’ll see them in the thousands on an infested tree, but they always show up late to the party; it’s part of their survival. They wait until populations can support their larval development. Adults eat a few, lay eggs and leave. While the larva are voracious, aphids recognize them and use defence mechanisms like kicking, walking away or dropping from the plant. Vermiform larva (worm like) like Aphidoletes or the hoverfly do not illicit aphid defence mechanisms and are proven to out-perform ladybugs in aphid predation larva to larva. Combine that with a shorter life-cycle (two weeks for Aphidoletes) and you get a massively-efficient knockdown of aphids. Plus, as Aphidoletes will almost only eat aphids, it can be released as a preventative (when aphid numbers are low) and they will find and eliminate them.
So there you have it – a non-exhaustive list of reasons not to buy ladybugs.
I will however add this: “ladybugs” is a relatively poor term. We associate it with the red, orange and yellow round bodied beetles, but sometimes the term includes all coccinellidae beetles (round bodied shape). Some of these (typically black) are commercially reared and target other pests, like Stethorus punctillum for Spider mite control and Delphastus catalinae for whitefly control. These are lab-reared, and top predators of their specific hosts, so of course you can buy those. Also available is Crytolaemus montrouzieri to control some mealybug species.
If you absolutely need to control aphids, please source out the right beneficial insect. But as always, remember that aphids are food for a huge number of predators – and they WILL show up. Planting a variety of plants for bio-diversity should be equated with allowing pest populations to exist to help with the bio-diversity of natural predators.
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