Speaking about garden pest control, ground beetles are one of the most beneficial insects there, although it must be admitted, they probably have bad breath.
That’s because these beetles eat slugs! Most ground beetles only eat slug eggs and baby slugs, but one particularly voracious variety is called the “slug-snail destroyer,” and it takes on some big ones.
I love ground beetles. They are kind of like little living tanks that deploy during the night and lay waste to slug eggs, snails, potato beetles, and cutworms.There are nearly 2500 different species of ground beetles in North America. Most ground beetles do good work, as evidenced by the common names of some beetle species; my favorites being caterpillar hunter (Calosoma scrutator) and eastern snail eater (Scaphinotus elevatus).
Turn over a rock or log, and you’ll see dark, shiny beetles running for cover – ground beetles. The best way to get to know the ground beetles is to observe some up close. Since most are nocturnal, you can usually find them hiding under boards or stepping stones during the day.
Ground beetles live in almost every terrestrial habitat on earth. Worldwide, about 40,000 species in the family Carabidae have been described and named. In North America, the ground beetles number well over 2,000.
The greatest nightmare of most insects that inhabit garden soils is the ground beetle. Ground beetles are very common insects which develop as predators, dispatching cutworms, beetle larvae, and other common pests with their strong, hooked jaws.Their mane reflects the fact that although they are highly active insects, most ground beetles are poor climbers and are restricted to areas around the soil surface.
Ground beetles are typically dark brown or black and somewhat shiny, although a few take on brilliant blue and green coloration. They are elongate in body form and the jaws are prominent.Because the are active only at night, ground beetles beneficial activities often are under appreciated. Gardeners sometimes may encounter a few when flipping over rocks, boards or other debris causing the fast moving beetles to scatter for cover.
Why they’re good as garden pest control
Garden pests killer in two stages of its lifecycle, this beetle enjoys snails, slugs, cutworms, gypsy moth larvae, root maggots, tent caterpillars, fly maggots and other garden and household pests, crushing them with powerful chewing mouthparts. Larvae feed for several weeks, then pupate in the soil. Adults are able to live two to three years.
They’re often found in moist to wet locations. Some types exhibit defensive behavior (like emitting strong odors) when disturbed. They’re fast runners. These beetles are sometimes attracted to lights and find their way inside the house. If you find one indoors, carry it outside and release it. It’s a good guy.
Ground beetles bear an unfortunate likeness to cockroaches, but the latter have longer antennae along with a different overall shape. Most of the helpful ground beetles are big, dark, and quick moving. They usually have nasty-looking mandibles and eyes on or close to the fronts of their heads.
To encourage these beetles to stay in your garden:
* Put out some stones and large rocks and plant some lasting plants in your garden for them to hide under. Provide stone pathways or patches of white clover, or leave a log to decay. They thrive under cover.
* Hedgerows are also an important habitat for ground beetles.
* Mulch. Ground beetles like to hideout underneath rocks, leaf litter, and woody debris—so adding a nice layer of wood chips or shredded leaves to ornamental garden beds and pathways provides plenty of habitat.
Don’t use insecticides. Ever. Insecticides, even organic ones like pyrethrum and rotenone, can kill ground beetles and other beneficial insects, which upsets the predator/prey balance in your garden. Attracting a diverse range of beneficial insects is a much better pest control strategy!
Want to know more about garden pest control? Then put your question here.
Tweet me in Tweeter and follow me on Facebook.
Yours truly, Polly – Organic Gardener
{ 15 comments… read them below or add one }
Another lovely critter that feeds on slugs is the sharptail snake, commonly called a red racer. They’re a small snake, often confused with earthworms due to their color and size. A pinkish, coppery brown color, they are most easily recognized by the black tread-like markings across their bellies. The largest one I ever saw was probably less than a foot long. Be careful when weedeating in something like Vinca during the cold weather when snakes aren’t active. If you try to take the vegetation down to the ground, you may very well hit the little sharptails huddled under the vegetation and leaflitter.
Hi, I just wanted to let you know that I enjoyed this article. Ground beetles are truly a good way to control garden slugs. If it is okay, I’d like to link to this page from my blog. Please let me know, thanks.
Hello. I am interested in the organic gardening and interestingly me what yet insects will be useful in such garden.
Yuriy, there are many insects that are helpful such as soldier beetles, mantids, predatory mites, lacewings and lady bird beetles to name a few. If you live in the US, you probably have a master gardener group in your county. You should be able to find them in the local phone book under county listings as part of the university extension service and county ag office. They can provide information including identifying any insects you bring in. Please make sure they’re in a container that will hold them securely yet let them breath.
http://www.ipm.ucdavis.edu/ is the address for the Integrated Pest Management site of the University of California but I would suggest you use the IPM site for your state university as they will be more familiar with your local indigenous species. Doing a web search for beneficial insects will provide a wealth of information. And if you happen to buy ladybugs at a store, be sure to refrigerate them for at least several hours if not for days and release them at night. Otherwise they will simply fly away and make other yards their home.
I read your post about pest control and wanted to mention that I recently launched http://www.pest-control.com and have been trying to spread the word. If possible, I would like to discuss helping me out with a link to our new site.
There is a new, innovative, yet simple, copper solution to slug problems that is 100% eco-friendly and effective. It also requires no maintenance. The Slug Shield. com
@Grateful Gardener The slug shield is a new twist on the old copper strip that is placed around a bed in order to deter slugs and snails with an electrostatic charge. However it seems to be designed more as a moneymaking gimmick than something to make gardeners grateful. Paying more than a dollar per plant for snail protection sounds very expensive and also very time consuming.
Twisting a bunch of copper wires, which is obviously what this product is, around the stem of each plant would take a very big effort for anyone with a nice bed of hostas. And buying one of these for every hosta, not to mention all the other plants would be very time consuming and expensive indeed. It also would not protect the hosta from any slugs or snails that climbed onto any leaves that were touching the ground, as hosta leaves do.
Surrounding an entire bed of hostas with a strip of copper would stop slugs and snails from entering the bed and it would cost a fraction of the cost of surrounding it with your little wires. But either one would also stop the slugs and snails already in the bed from leaving. And any eggs in the soil would still hatch. And neither would do anything to the creatures except stop them from crossing the copper barrier. They definitely won’t kill them.
And it does turn out that the ferrous sulfate might not be friendly toward birds. So while it doesn’t harm people or pets (non-avian pets, at least) and actually feeds the soil with necessary iron, two very good things, it’s possible that it can harm bird populations. And birds are facing too many threats as it is.
So the best possible control is natural. That is letting creatures like ground beetles and sharptail snakes that normally feed on slugs continue to do so. Ducks, chickens and other domestic fowl are also a great natural control.
Using comment forums for free advertising has become rather commonplace on the internet. But this method of free advertising also allows people to point out what’s wrong with the products being advertised, unlike paid ads. This allows people to give better alternatives to the products being advertised and to let others know when a product has been created solely for the purpose of bilking people out of money, as the slug shield seems very obviously designed to do.
Have you tried the slug shield?
I have used slug shields and they worked for me. The cost/reward ratio was low – that is they were absolutely worth the purchase price. I saved my plants that otherwise would have been decimated and lost.
I used to use something like Sluggo. I didn’t like applying it so regularly, like each time it rained or every 10 days. I didn’t really feel that it was non-toxic, and certainly not organic – as a biologist I wondered how something non-toxic would kill one organism and have no effect on any other organisms.
Look in to EDTA as an ‘inert’ ingredient in these products – that actually explains how they do work. That is a very toxic combination. In Australia they require more transparent labeling and EDTA is actually listed. So this stuff is toxic and that is not something I want to sprinkle around my plants and into my land.
I love the idea of IPM. We need more of it. Slug Shields, however, worked for me overnight (literally) and the application was very targeted. It took me about 1 minute to apply the slug shield to a plant and that was it for the entire season. I am actually going to re-use them next season too!
I am happy to use slug shields and tell people about them. I am grateful for my garden and for this simple idea that works for me. They are the best non-toxic, full season protection that I have used and they were worth the $12.
Ground beetles are truly a good way to control garden slugs. Thanks for helping. Very informative and useful!
Thank you for this informative article. As I prepare to fight the lugs that devastated my garden last summer, I think I will actually try the slug shield for the more vulnerable caladiums. I do not have large beds of hundreds of plants, so this would add extra protection to the few caladiums I grow. But I also want to protect all the wild plants that grow in the garden, so I also want to use the beetles. I have two questions though. First, where can I get the kind of ground beetles that eat slugs? And second, would they also eat earthworms?
Thank you!
J
So what type of ground beetle eats snails? and where can we buy em? I live in New jersey, and i cant find a source.
It is Scaphinotus angusticollis that is very popular in Pacific Northwest, Seattle area. I don’t know about New Jersey, sorry.
ok, thanks polly, i’m going to do the copper instead then.
oh wait wait, that pic above, the beetle looks like a roly poly? are there some that are like that that go after slugs? cuz i thought i had killed 2 or so roly poly look alikes, of which i thought they were, in which case i killed slug killers. hmmmm
or nvm, it appears to have only legs up to it’s midsection. bleh. the ones i killed had legs all the way back