Wednesday, May 11, 2011

BUGS: THE GOOD...

            Recently Tim sent me an email. (It’s ridiculous how we email back and forth across the kitchen table. It’s not as if we don’t actually talk to each other: more often than not we’re emailing and chatting about what we’re emailing at the same time. My son Sam aptly calls our increasing reliance on machines for interpersonal communication “going over to the Dark Side.” He used the phrase in an email, of course.) Anyway. Tim’s recent email concerned the imminent arrival of the Great Southern Brood of 13-year cicadas. No one knows for sure why some species of these loud but largely harmless insects emerge from their pupae all at once. Some scientists think it’s a survival thing: if a skillion of them appear at the same time, predators can’t possibly kill them all.

A 13-year cicada
"Mr. DeMille, I'm ready for my closeup."

Area affected by the
Great Southern [Cicada]
Brood of 2011
(in pink)

           



             You can see from the map that southeastern North Carolina is unlikely to receive a visitation. We missed the 17-year cicadas several years back as well. I remember traveling to visit my Marylander cousins that particular July and noting the tips of tree branches broken off all along the I-95 North corridor starting in Virginia. Apparently, the damage came from cicadas’ egg-laying behavior; it was largely cosmetic as the larvae migrate to the ground to pupate. For over a decade.

              Isn’t nature wonderful?

            Got me thinking about bugs, and the general aversion they arouse in humans. We’d be in sorry shape without them, up to our ears in waste and skin sloughings. Maybe it’s all the Japanese horror movies we of a certain age saw as children (remember Mothra? And the truly weird Gamera the Flying Turtle, Friend of Children?) or the insectile aliens of, well, the “Alien” movies and “Independence Day.” Personally, as long as they don’t turn up in my food or my bed, suck my blood or take up residence in my hair, I think insects and their relatives the arachnids are kind of nifty. And because I’d like you to re-examine your knee-jerk reactions to these tiny marvels of design and efficiency, I thought I’d spend some time reintroducing you to a few of them you’re likely to encounter in the garden.

            Today we’ll cover some familiar good bugs in their perhaps less familiar larval forms. Next post will cover some of the garden’s most pernicious insect pests, and then we’ll move on to the boths and the neithers on May 19.

Ladybug baby

Ladybug mama
           
            This first fellow is a ladybug larva. Not as pretty as his mama, is he? Nonetheless, this voracious little aphid-hunter can consume up to 50 times its weight a day. Not too shabby, huh? So before you do anything to get rid of aphids, check for these guys: if you see them, put away the sprayer. Nature is on the job, and will clear up the problem by itself. This is especially true of the annual infestation of young river birch (Betula nigra) apt to occur right about now.

The golden garden spider,
beautiful and good to have around
          Here we have the beautiful golden garden spider. Now, don’t go all cringy. The fact of the matter is that almost every spider you see around the garden is beneficial. They all eat other insects although their acquision methods vary, from digging burrows to hide in, to sitting very still and jumping out at prey, or—like E.B. White’s Charlotte, who may have been inspired by a golden garden spider—by weaving sticky-stranded webs. While most any wild creature will bite if you frighten or threaten it, only a minuscule proportion of North American spiders are harmful to humans. I’m not saying you have to stop being afraid of them—Tim is—but do try to quit stomping or flushing every single one you come into contact with. When an arachnid detours through our house these days, Tim will gingerly sweep it into the dustpan and carry it outside (or, depending on its size, call me to effect the evacuation).

Black swallowtail butterfly baby
The black swallowtail butterfly mama
          
             
          







           



            On to something a little less creepy (so to speak). This beautiful black swallowtail butterfly emerges from the chrysalis of this equally beautiful caterpillar. Yes, it’s a bit of a stretch to call foliage-tattering caterpillars beneficials, but without them, there are no butterflies. It’s worth it to find a decent butterfly book or website with pictures of the larval stages. It’s also worth it to include plants they like to eat in your garden. I grow parsley and fennel for swallowtails, passionflower for Gulf fritillaries, butterfly weed (Asclepias spp) for monarchs, and an extra tomato or two for tobacco hornworms. These last, by the way, serve two useful purposes: 1) they metamorphose into the spectacular nighttime pollinators, Carolina sphinx moths; and 2) they themselves host the larvae of obviously beneficial tachinid flies and various genera of parasitic wasps, which hatch into the hornworm from those white rice-like capsules you sometimes see on the caterpillars’ backs. It’s a satisfying reminder that there is balance in the universe as your tomatoes’ foliage disappears.

Tobacco hornworm facing a grim fate
from baby parasitic wasps

Our friend, the tiny tachinid fly



       
   

           


            Now let’s talk about the Apiaceae (the family name of bees and wasps). All of these creatures pollinate something or other, so it would behoove us to let them alone to get on with it. Despite the bad rep, many don’t even have stingers. If you’re allergic to bee venom, follow your doctor’s instructions for avoiding and evading those that sting: it helps to keep away from flowery-scented soaps, shampoos, perfumes and deodorants. Still, if you don’t count African killer bees, few species are aggressive unless frightened or their home and/or young threatened. (Sound familiar?) Not all bees and wasps are social creatures either, doing very well without hives or nests to service or queens to kowtow to. Here are a few solitary bees with whom you’re probably acquainted.

A mason bee

A handy bee comparison

           








         Speaking of pollinators, mark your calendar—the Great Sunflower Project’s Great Bee Count of 2011 is scheduled for July 16th. (Check out the February 4th post, “For the Birds.”) If you haven’t already planted your annual ‘Lemon Queen’ sunflowers for the season, now would be a good time so they’ll be up and blooming for the Great Day. Since my indoor starts came to naught, I stuck 41 seeds in the ground today. If you need seeds, both Baker Creek Organic Seeds and Renee’s Garden sell them: if you mention the code FR225A, Renee will donate a portion of the proceeds to the Project. Which is pretty darn nice of her.

            Unsure just what is putting holes in your foliage or nibbling on your fruit? Some good resources to turn to follow, before the wholesale slaughter begins.

1.    Jessica Walliser’s Good Bug, Bad Bug: Who’s Who, What They Do, and How to Manage Them Organically (2008, St. Lynn’s Press, Pittsburgh, PA), an outdoor-friendly little book with good illustrations of some of the most common six- and eight-legged garden visitors.

2.  Garden Insects of North America by Whitney Cranshaw (2004, Princeton University Press, Princeton, NJ), a more scholarly work with loads of helpful pictures of various life stages and damages inflicted. Cranshaw also offers more in-depth information about families, life cycles, host plants and ranges than Walliser: good to go to after identifying your bug, or just to page through.

3.    Mac’s Field Guides, laminated 7 by 11½” sheets picturing good bugs on one side and bad bugs on the other, divvied up by geographic region. Each comes with a nice hole at the top so you can hang it in your garden shed or garage for handy reference. I have a copy of Mac’s Field Guide to the Good/Bad Bugs of the Southeast (2000, The Mountaineers Books, Seattle, WA).

4.   Contact your local Cooperative Extension Office or your state’s land-grant university’s plant pathology department. North Carolinians can call on the expertise of the Plant Disease and Insect Clinic out of NC State (see the January 27th post, “Bugged”). My article on the PDIC is due out in the June issue of Carolina Gardener magazine, by the way—look for it starting about now at your local Borders (if it’s still operating) or at fine garden centers all over the Carolinas.

More bugs next time. Thanks for dropping by.

                                                                        Kathy

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