Skip to main content

Coneflower-cutting weevil

One of our showiest prairie plants is the Purple Coneflower, Echinacea purpurea. They aren't particularly common here in Ohio, at least in a wild state, and finding their rosy-purple blooms in prairie remnants is always a treat.

For years I've noticed that something attacks coneflowers in a most interesting way, and it wasn't until a recent field trip that I learned who the culprit was. We had seen some coneflower damage in a neat little patch of prairie in Clark County, and naturalist extraordinaire Jim Davidson knew, in a general way, who the attacker was.

Perhaps you've seen this sort of thing. It's as if a mad gardener with nicely sharpened clippers has come along and clipped the flower, leaving it to dangle. The cuts are perfectly straight and quite well done.

Well, it turns out the mad clipping is the work of a tiny weevil. These small beetles apparently saw through the coneflower stem, and lay their eggs in the gooey sap which forms at the wound. Once they mature, the blackish, long-beaked adults clamber down to the dangling flower and commence feeding.

The dark adult weevils can be seen here, frolicking amongst the disk flowers. If you see this sort of damage on your local Purple Coneflowers, inspect the wilting blossoms and you should find the adult weevils tucked within. They're devilishly hard to get good shots of, as if overly molested they drop out of there like cannon shot and disappear. When I did manage to get one in the hand it was in perpetual motion and I'd probably have had to conk one over the head to subdue it into stillness.

A bit closer in, and you can see the adult weevils glistening from within the flower. I wish I knew more about them, including the exact species. If anyone knows, send a shout out. The whole modus operandi of these weevils intrigues me. I can see cutting the stem - quite an operation in itself for such a small beast! That stimulates sap flow which hides and nourishes the larval weevils.

But it obviously does the flower in. Maybe that creates the perfect conditions for other predators to invade the dying flower, such as aphids or other wee creatures, and the adult weevils feed on those. Or perhaps it causes the developing seeds to atrophy and become easier to eat, better meals.

Whatever the case, the complexity of the insect world never ceases to amaze me.


Steve Willson said…
Jim, I see the weevils doing the same thing to Whorled Rosinweed, Ashy Sunflower and Prairie Dock. I've always wondered if it was a strategy to reduce sap flow to the part of the plant they were feeding on. Some insects that feed on milkweeds use this method to get a meal without a mouth full of sap. I've also witnessed these cut flowers rain weevils as the insects used gravity to power their escape.
Anonymous said…
OSU recommends taking the broken flower and tossing it into soapy water. This will kill the weevils and perhaps prevent the problem in the future. I'm getting more angry at this critter than at the ever present japanese beetles!!!
Kim Landsbergen said…

Popular posts from this blog

The Pinching Beetle, a rather brutish looking bug

The world is awash in beetles, and they come in all shapes and sizes. Few of them can match the intimidation factor of a Pinching Beetle, Lucanus capreolus, though. Those formidable looking mandibles look like they could slice off a finger.

Today was one of those coolly diverse days. I started off down in Fayette County, visiting the farm of a friend. He has restored about 25 acres of wetlands, and the response by the animal community has been nothing short of phenomenal. Blizzards of dragonflies of many species, amphibians galore, and nesting Blue-winged Teal, Pied-billed Grebe, and Sora. Among MANY other things. And all in a short two years. Add water and they will come.

Then, working my way home, I ducked into a Madison County cemetery that has a thriving population of Thirteen-lined Ground Squirrels, and shot images of our native prairie dog. Then, I stopped at a spot along Little Darby Creek, waded on in, and procured some pretty nice shots of various stream bluets and dancers. …

Calliope Hummingbird in central Ohio!

A hatch-year male Calliope Hummingbird strikes a pose. Small but tough, the hummingbird was feeding actively yesterday in 39 F temperatures. It frequents feeders and gardens at a home in Delaware County, Ohio, about a half-hour north of Columbus.

Fortunately, the wayward hummer appeared at the home of Tania and Corey Perry. Tania is a birder, and knew right away that the hummingbird was something special. For a while, the identification was up in the air, which isn't surprising. The Calliope Hummingbird used to be placed in its own genus, Stellula, but has recently been submerged into the genus Selasphorus, which includes Allen's, Broad-tailed, and Rufous hummingbirds. The latter two, especially, are quite similar to the Calliope in subadult plumage. Rufous is the default "vagrant" hummingbird here, with dozens of records and birds turning up annually. There is but one Ohio record of Allen's Hummingbird, from late fall/early winter 2009. Ditto the Calliope Hummi…

Snowy owl photography tactics - and things NOT to do

A gorgeous juvenile female snowy owl briefly catches your narrator with its piercing gaze. It's doing its Linda Blair/Exorcist trick - twisting its head 180 degrees to look straight behind. Owls have 14 neck vertebrae - double our number - which allows them such flexibility.

These visitors from the high arctic have irrupted big time into Ohio and adjacent regions, with new birds coming to light nearly every day. Probably 80 or so have thus far been reported in the state, and some of them have stuck around favored spots and become local celebrities.

I went to visit one of these birds this morning - the animal above, which was found last Friday by Doug Overacker and Julie Karlson at C.J. Brown Reservoir near Springfield. In the four days since its discovery, many people have visited as is nearly always the case when one of these white wonders appears near a large population center or is otherwise very accessible.

And as is always the case, people want to photograph the owls. And th…