Lightning bugs eat WHAT??

Who doesn’t like lightning bugs, the quintessential sign of summer? Of all that I learned at Saturday’s Winter Gardening Fair, my favorite tidbit is another reason to love this beneficial beetle. The next time my kids ask what lightning bugs eat, I’ll know, thanks to entomologist Donald Lewis, whose session, “The Good, the Bad and the Buggly,” was one of three workshops I attended at the gardening fair.

Here’s more of what Lewis, from Iowa State University’s extension, had to say.

On earwigs:

It’s a myth that earwigs crawl into a sleeping person’s ears to lay its eggs and they don’t burrow into your brain (whew!) Their name comes from a habit they had in the damp castles of Europe of crawling into the white wigs of the castle’s inhabitants and then wandering into the wig-wearer’s ears. Of more relevance to our time,  earwigs, identifiable by pincers on their tailend, are both beneficial, as they feed on decaying matter, and a pest, as they also nibble on foliage.

White grubs and Japanese beetles:

White grubs are the larval stage of various types of June bugs. Most of those in Iowa are the “masked chafer,” and more and more, the dreaded (editor’s note) Japanese beetle. The grubs live in lawns and chew the roots off grass. Secondary damage is done when raccoons and skunks scavenge for this “land shrimp” and tear the turf to get at the grubs. Moles, by the way, don’t indicate that your lawn has grubs. Their favorite meal is earthworms. There are various chemicals to rid lawns of grubs and to spray on the adult beetles, but just getting rid of the grubs won’t eradicate problems with the adults, because even if your lawn is grub-free, adult beetles – Japanese beetles, at least – can come from far away to dine on your roses, raspberry bushes and 350 other types of plants. Hand-picking the adults works best when done early in the season, as their chewing releases a scent to other Japanese beetles of where to find their next meal. Lewis said what you do with them after you pick them off is your choice: hammer, etc. Mine is to knock them into a container of soapy water. If you use plain water, they can swim around for several days and be none the worse off for your trouble.


 Aha! This is where the lightning bugs come in. Placing copper strips or pennies in your hosta – a favorite target of Iowa’s gray garden slugs – hasn’t been proven to prevent the slugs’ damage. But lightning bugs, in their larval stage, prey on slugs. Lightning bugs also eat other insect larvae and snails. What a beneficial beetle!

There was so much more I learned at the gardening fair. From Linn County Master Gardener Lu Barron – you might know her as one of our Linn County Supervisors – I found out why my peonies might not be blooming. Too much shade, too much competition from other plants, buds nipped by a late frost or too much nitrogen fertilizer are among the possible reasons. I also learned the best way to plant peonies – with eyes 1 to 2 inches below the soil line.

All of the presenters undoubtedly put quite a bit of preparation into their sessions, but I don’t know of anyone who had more work to do than Master Gardener Nancy Sutherland, who labeled and bundled dozens and dozens of tiny dried flowers so each of the attendees at her “Everlastings” workshop could leave with a whole box to take home and examine. Sutherland and other Master Gardeners can be found at the Lowe Park demonstration gardens in Marion, as soon as the weather warms.

Finally, what a great presentation by keynote speaker, Melinda Myers! Some of my previous posts (including excerpts from my interview with Melinda, if you want to hear her for yourself) address her topic of attracting butterflies and birds to your garden.  But I think my favorite quote from her speech was about how to get children interested in gardening. “Even if you don’t enjoy them, bugs get kids in the garden,” she said. “And the creepier the bugs are, sometimes, the better.”  

1 Response so far »

  1. 1

    Sandy Hunter said,

    I also attended the Winter Garden Fest. I have attend it every year from the start. I truly enjoyed the information on Bats and bat houses. I plan on installing a fewbat houses this spring. I’m a Master Gardener from Black Hawk County, and give a five high to the Linn County MG’s!!! Great Job!!

Comment RSS · TrackBack URI

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: