(Lady) Beetlemania

We’re heading into winter—some of us in the US more than others–which means that you may soon find Asian lady beetles (commonly known as lady bugs) on your windows and in your light fixtures. Although they can be a nuisance, and can stink and stain surfaces if they’re crushed, they don’t do any harm. They’re just looking for a slightly protected space to hibernate.

Asian lady beetles. Photo courtesy of University of Minnesota Extension, http://www.extension.umn.edu/garden/insects/find/multicolored-asian-lady-beetles/

The Asian lady beetles are roughly a quarter-inch long, but their appearance varies. Their forewings may be yellow, orange, beige, or bright red. Ten black spots typically decorate each forewing, but it’s not uncommon for the beetles to have fewer spots, faded spots, or no spots at all. In the spring and summer, these lady beetles prey on aphids and scale insects, benefitting home horticultural and commercial agricultural crops alike. Cooling temperatures signal to adult lady beetles that it’s time to find a protected site where they can spend the winter.

There’s A Place

The lady beetles favor warm and sunny sides of buildings, as well as exposed, light-colored buildings, but any protected location offers some appeal. They may move indoors through cracks in weather stripping, or small gaps around window and door casings or through attic and soffit vents.

I’ll Be Back

You may have noticed that beetles frequently pick the same sites to overwinter. Research suggests that the beetles use chemical cues, possibly from beetle feces or attractant pheromones, to locate the particular crevice they want to inhabit, whether that’s in a tree or in your siding. Although they may seem to permanently inhabit, say, your overhead kitchen light fixture, they actually can’t survive for long periods within the centrally-heated rooms of your house. They prefer to shelter in wall voids or semi-insulated spaces. But they become more active on warm days and move towards bright surfaces, like light-colored walls or ceilings, or lighting fixtures or windowsills. That’s when you notice them.

It’s possible that large numbers of beetles may cause air quality problems indoors that could trigger allergies and/or asthmatic reactions. But fortunately for allergy sufferers, this lady beetle does not reproduce indoors. When the warmer temperatures of spring come around, they’ll move outside in search of food. And they don’t eat wood, so they won’t cause structural damage to your house or to your furniture.

Lady beetles clustered in doorframe. Photo courtesy of Iowa State University IPM. http://www.ipm.iastate.edu/ipm/icm/2007/3-26/asianladybeetle.html

If You’ve Got Trouble Here, There, and Everywhere, and Think It’s All Too Much, Remember All Things Must Pass. And I’m Here to Help.

What can you do to control the invasion?

You Can’t Do That

Don’t reach for the pesticides. You’ll waste your money. Pesticides are not very effective at halting beetle invasions. Spraying and fogging can be hazardous to your and your pets’ health, and excessive use may present fire hazards. Biological controls, like tachnid flies, offer limited effectiveness.

Blacklight traps can catch beetles well in some situations. USDA scientists in Georgia developed a trap that uses no insecticide and it catches the beetles alive for future release or disposal. The trap is about 12″ x 24″ and reportedly can be easily assembled or disassembled. Learn how you can build your own blacklight trap following the USDA’s instructions.

She Came In Through the Bathroom Window

The best approach is to exclude the beetles. Seal around windows, doors, siding, and fascia boards with caulk, weather stripping, or foam sealers. Snugly-fitting sweeps or thresholds on exterior doors can prevent beetles from crawling through those gaps. Keep your window screens in good condition and consider adding insect screens to attic and soffit vents. And as a bonus, doing those things will prevent cold air leaking into your house, saving you money on your heating bills and conserving energy.

Some people vacuum up the beetles. If you like this idea, try a tactic recommended by Dr. Susan Jones of The Ohio State University: Insert a knee-high nylon stocking into the vacuum’s extension hose and secure it with a rubber band. Then reattach the hose and vacuum up the insects. The beetles will be trapped inside the stocking. Remove the rubber band and secure it around the open end of the stocking, or simply tie a knot in the end. Take them outdoors to a protected space under a porch, deck, or shed, and let them hibernate there. In the spring, release them into your garden near aphid-infested plants. If the stocking approach is too much trouble, just use your regular vacuum bag, but be sure to remove it promptly and dispose of it outdoors.


For more information:


Carolina wolf spiders, or Halloween Arrives Early

I got a bit of a shock the other morning when I went to pick up a stray bit of laundry on the bedroom floor and found this fellow scrambling around in it:

big scary spider aerial

I trapped her in a clear plastic container so I could examine her more carefully. As a result, the photos are not as sharp as they might be.

The first thing you’ll notice is that she’s huge. That’s part of what makes me believe she’s a female. If I’m correct in my identification, she is a female Hogna carolinensis, or Carolina wolf spider. Females of this species have bodies between 22-35 mm (.8–1.4 in), while males are smaller, at 18-20 mm (3/4″) in body length. I would estimate this one to be close to 35mm long, about the length of my thumb from the first joint to the base of my thumbnail.

Carolina wolf spider (Hogna carolinensis)

Carolina wolf spider (Hogna carolinensis)

She’s also quite beautiful, with elaborate markings on her cephalothorax and slightly less extensive markings on her abdomen. Her legs are hairy but without stripes. She scrambled frantically inside her plastic trap and was strong enough to push the container around on the wood floor when I didn’t hold it down.

Carolina wolf spiders are the largest wolf spiders in North America (oh, good!), and they are hunters, not passive web-weavers. They’ll eat large insects and even small rodents. They like arid areas, which perhaps is why I found this one inside my house. It’s been really wet lately; perhaps she needed somewhere to dry out. I’d rather not reflect on what she may have been eating while I sleep.

big scary spider 2Carolina wolf spiders dig burrows six inches deep in which they deposit egg sacs of 100-150 eggs. Wanting to find neither a six-inch-deep hole in my house nor 150 baby spiders like her, I slipped a piece of tin foil beneath the edge of the container, onto which she jumped, then slid it across the opening to secure her within the container. I took her outside and dropped her into the vegetable garden, where I hope she’ll terrorize every flea beetle in sight.

Something beneficial: Praying mantis

The other evening, I stepped out to purge my pathway of spotted spurge. And as I did a little deadheaing of the Rudbeckias, I noticed something:

praying mantis

A praying mantis.

These are terrific insects to have in the garden. Beyond being fascinating to watch, they eat other insects that are less desirable, such as aphids and grasshoppers. They also eat beneficial insects like lacewings and ladybugs, but as I have far more aphids than lacewings, I feel positive on balance about this fellow’s presence.

praying mantis closeup

Their heads can apparently swivel 180 degrees to watch their prey, and they have a visual range of up to 65 feet. These predatory insects typically eat their prey alive, although if the prey vigorously resists, the mantis will often start with its victim’s head in order to make the meal a bit more relaxing.

I couldn’t discern what this fellow was watching, but I wouldn’t want to be it, whatever it was.

praying mantis recumbent

My very hungry caterpillar(s)

(an homage to Eric Carle)

At some point last summer, a butterfly lay an egg on a leaf.

One morning, when I wasn’t watching, out of the egg came a tiny and very hungry caterpillar. Then his brother hatched. And his sister. And his other sister…

They started to look for some food.

On Monday they ate through one Rosa ‘Gertrude Jekyll.’ But they were still hungry.

very hungry caterpillars

On Tuesday, they ate through some gardenias. But they were still hungry.

gardenia 1

On Wednesday, they ate through three 6-foot Osmanthus. But they were still hungry.

osmanthus 3

On Thursday, they ate through a Heuchera. But they were still hungry.

heuchera 2

You know the rest of the story.

We all love butterflies. We want them to fill our gardens and delight our children and ourselves. But if we want them, we had better accept that we must also have caterpillars. As depressed as the chewed-up foliage leaves me, I won’t reach for any sprays. Soon they will be big, fat, sleepy caterpillars and I can pass some time with my kids finding cocoons. I grow several plants that are favorite hosts of different butterfly species: rue (Ruta graveolens), favored by the Old World swallowtail;  bronze fennel (Foeniculum vulgare), favored by the Anise swallowtail; butterfly bush (Buddleja), Senna marilandica, Golden Alexanders (Zizia aurea), Joe Pye weed (Eupatorium purpureum) and others. When caterpillar season is over I will cut off the decimated foliage, and wait for the butterflies to emerge.