A guide to summer insects of the garden, including dragonflies, spiders, froghoppers, water striders, praying mantises and crane flies.
An introduction to summer insects of the garden.
What one poet called, "All the live murmur of a summer's day," has always seemed to me more of a general buzzzzzzzz and hummmmm. Birds and other creatures chime in from time to time, but it's insects that dominate summer's symphony, day and night. Little wonder, when you stop to consider the sheer numbers. Of the 1.7 million known species on planet Earth, 1 million are insects. At least 100,000 different kinds fly, creep or crawl in North America.
This is not especially good news to most humans, who tend to associate insects with bites, stings and damaged crops. True, we can appreciate the butterflies painting our days and the crickets serenading our nights. But think "summer insects" in general and what images arise? Enraged bees and wasps; bloodthirsty mosquitoes; swarming gnats; invading ants; leaf-eating, sap-sucking garden gluttons.
To strike a blow against this bias, I thought I'd remind you of some of summer's other insects — summer insects of the garden that are beneficial, all harmless and fascinating.
Dragons and Damsels
If George Barris, king of custom hot rods, designed insects, he would've come up with dragonflies and damselflies. They're quick: zero to 60 mph forward or backward. The power plant: four wings, in independent pairs, beating 25 to 40 times a second. Colors? Metalflake green, candy apple red, cool ivory, diamond dust blue, copper glow. Plus, outrageous options on wing and body shapes, stripes and spots.
Three hundred million years ago, dragonflies with 2%-foot wingspans zipped about primeval swamps. Today's species (there are about 450 in North America) are considerably smaller but impressive nonetheless, shimmering in the sun, wings whirring, as they snag buggy prey on the fly. They mate in midair, too, the male grasping the female by the neck with his pincers as she curves her abdomen to him. Eventually the female dips her fertilized eggs into the water of a pond or stream. We think of dragonflies as aerial creatures, but they spend most of their lives — one to three years — underwater as nymphs, eating small insects and larvae. Flying adults live only about eight weeks. How do you tell a dragon from a damsel? A resting dragonfly's wings extend flat out to the sides, like an airplane's. Damselflies hold their wings clasped together vertically over their bodies.
Dew Drop Inn
Spiders, of course, are not insects but arachnids, creatures with two additional legs. Still, most of us think of them as "bugs" in the same nontechnical sense as other flying and crawling invertebrates.
My favorites are the grass spiders, funnel-web weavers that emerge in spring, pouring dozens at a time from an egg sac produced the previous autumn. The tiny trappers disperse, each going off to weave a small, flat tapestry in leaf litter or among blades of grass. As summer progresses, the webs become larger and so, too, do the brownish spiders within, eventually reaching half an inch.
Garden spiders are conspicuous, centered in their sticky orb webs. The grass spider, though, hides at the edge of its sprawling web, lurking inside a silken cave: the hole at the bottom of the funnel. Tickle the web with a twig and it'll come dashing out to catch — well, minus the human trickery — grasshoppers, moths and any other insects that wander onto the welcome mat. The web isn't sticky, but slows prey down long enough for the spider to grab dinner and drag it to the den.I'm fond of these webs. For on a summer morning they glisten with dew, providing another example of Nature's artistry and a good excuse not to mow the lawn just yet.
Who Spit on the Grass?
Venture into a meadow on a hot summer's day and you'll likely see globs of froth clinging to the tall grass, long after the morning's dew has vanished. The foam looks like whipped egg whites. Rub some between your fingers — it's slippery, like soap. No, the bubbles are not frog spit, snake spit, or cuckoo spit, contrary to common kidlore. Carefully wipe away the foam and you'll find the real culprit: a plump, dark-eyed, green creature about the size of a sesame seed — a froghopper nymph. The froghopper is named for the adult insect's squatty shape, pop eyes and leaping ability. The expectorating nymph is better known as a spittlebug.
Spittlebugs face head down on a leaf or stem, plunge a pointed beak into vegetative tissue and suck sap through their bodies, extracting nutrients. As the liquid comes out the other end, mixed with soapy abdominal secretions, the insect puffs air into it through a bellowslike organ, blowing bubbles. The froth flows down and around the nymph, keeping it cool, moist and hidden from predators. In fall, adult female froghoppers lay eggs at the junctures of stems and leaves, ensuring next year's crop of bubbly bugs.
Walking on Water
"Do make waves" might be the motto of the ever-amorous water strider, which lives not in water but on it, and communicates with significant others by sending wavelets of telltale frequencies rippling through the surface film. Males tap out come-on lines to potential mates and stay-away warnings to competitors; females respond in kind. Watch a water strider skitter about in staccato bursts, its middle pair of legs doing the rowing and the hind legs steering, its' short forelegs ready for catching prey. You can see each little foot pushing into the surface, dimpling but not breaking it. Most other insects — even much smaller, lighter kinds — sink and drown. Why not these special creatures, known to some as Jesus bugs?
Water striders are covered stem to stern and toe to toe with a layer of tiny, waxy, feathery hairs in which countless minuscule air bubbles are trapped. The hairy, airy coat holds water away as the insect glides along, safe and dry. Water striders can't bite humans, but small bugs unlucky enough to fall into the leggy insect's skating grounds are another matter. The water strider pierces prey with two hollow projections from its beak, injects an enzyme that liquefies the victim's insides and then sucks up the soup.
Say Your Prayers
"Watch out for that mule killer!" shouted my neighbor, an Appalachian old-timer I was helping trim shrubs. Heart pounding, I looked down to locate the monster, only to find a praying mantis, also sometimes called a "devil's horse" in these parts, gawking back.
The scary names are understandable, given the mantis' fierce, alien looks. There's something unsettling, too, in the leggy bushwhacker's ability to look over its shoulder at you; it's the only insect capable of doing so. Most impressive, though, is the creature's voracious appetite.
Using its lightning-quick spiked forelegs and jaws capable of crushing even armored beetles, a praying mantis will snatch and devour almost any insect in its path. The Chinese praying mantis — brought to this country in 1896 and the largest and most common of 18 kinds here — will even go after hummingbirds and lizards. And then, of course, there's the praying mantis' infamous cannibalistic tendency, reflected in the female's habit of eating the male as they mate.
Praying mantises are touted as effective pest controllers, but entomologists point out the predators also gobble helpful or generally desirable creatures, such as spiders, butterflies, moths, crickets and lacewings.
They come to our porches bounding softly feet first at our screen doors, bouncing up and down, up and down, as though their long legs were spring-loaded. They look for all the world like a mosquito on steroids: the same body shape, but up to 2 1/2 inches long, with wings 3 inches tip to tip. Surely a "mosquito" 20 times the size of your average skeeter inflicts a proportionately nastier bite, right?
Well, no. Crane flies can't bite, sting or suck blood at all. Fragile and largely beneficial, these creatures spend most of their brief adult lives searching for a mate. Still, so many people are terrified of them there's a even special word for the fear: tipulophobia.
The word is rooted in the insects' genus name, Tipula, of which there are hundreds of species in North America and several thousand worldwide. In some regions of the United States the larvae of two exotic species, recent arrivals from Europe that feed on certain plant roots, have become lawn pests. Most crane fly larvae, though, are aquatic and quite benign. They're favored fish food, and indicators of good stream health. Other types, also harmless, live in soil and leaf litter and are important decomposers. Birds gobble larvae and adults with relish.
Terry Krautwurst, a former senior editor for MOTHER EARTH NEWS, is a nature writer who explores the world from his home in the mountains of North Carolina.