

Bugs — the good, the bad and the ugly

January 3, 2014

It had to happen. After successful harvesting of the crops we are raising at Trafalgar Middle School garden, you wonder when the bugs will settle in and take over. Plant a garden and the insects will come. We have pulled up the finished cucumber and the zucchini vines. I have had to take time out from working the garden and Judith Pelitier has ably taken over the work with other Master Gardeners. She did alert me to the presence of white grubs munching away. An insect expert I am not. So they were busy smashing all they found.

Judith contacted the Ag Extension agent, Roy Beckford, and this is what he had to say. "Hi Judith, these grubs appear to be very possibly the larvae of the 'green fruit beetle.' They generally help to break down mulch or heavy soils to produce compost by eating and passing the cellulose through their bodies. They do not eat live plant roots in the way that 'white grubs' from the brown beetle do to lawns.

So I would not get rid of these grubs, but since the adults (green fruit beetles) eat ripe and rotten fruit, make sure to inform garden participants to harvest tomatoes before they are overripe, and rotten fruit should be disposed of quickly.

That said, it is your call; just note that removing them from mulch removes one of the most efficient sources of mulch break down from your soil system, so the whole thing will break down a bit slower."

This reminded me of the Master Gardener lessons about "Good Guys/ Bad Guys." Don't try to kill all bugs, or spray or spread chemical solutions indiscriminately, because you will kill the good bugs, too. The key is to learn the good bugs, and I must admit I had not learned of the "green fruit beetle" being a good guy. I loved finding them, with their bright emerald green shiny coats of armor. I just knew they were models for the attractive green scarab beetle jewelry. June beetle grubs look like a smaller version of the "green fruit" beetle and they do damage to lawns and grass. You'll find the "good" guys, fruit beetle grubs, in the compost pile.

On the other hand, Al, the teacher and director of the students club, loves all the cheery butterflies hovering around the cabbage family plants. I hope it's not too big a letdown when we tell him they are looking to lay eggs for their caterpillars to eat those plants. I am a big butterfly lover and will protect caterpillars in the garden and fruit trees, just plant enough to share. But, I've had them wipe out my whole crop of parsley, dill and fennel before I realized they were there. But cooking with a cabbage that has a bug (caterpillar) in it is ugly! Speaking of ugly, is there anyone who hasn't encountered a giant hornworm tomato caterpillar? If the worm is green, it is a "bad" worm. My mother-in-law refused to eat broccoli ever after she found a big green worm in a fresh broccoli head she was fixing for a meal.

Enough about the bad guys. Attracting beneficial insects is the best way to combat "the bad" and "the ugly." The top five beneficial garden insects and why they are beneficial are:

- Green lacewings larvae eat tons of aphids. Lacewings are common insects, found on weeds, row crops and shrubs, either greenish or brown, about 3/4 inches long with transparent veined wings. They are commonly called aphid lions and feed on aphids, other small insects and eggs.

- Lady bugs, (fly away home, your house is on fire and your children alone) both their larvae and the adults eat aphids, scale insects, thrips, mealy bugs, mites and other soft body insect pests as well as eggs. You can buy them in cottage cheese size containers at many garden centers.

- Assassin bugs, the James Bond of insects, brown or black, 1/2 to 1 inch in length, relentlessly hunt out predators, feeding on beetles and caterpillars. The head is elongated with a short, curved beak. Nymphs are just as effective in controlling pests as adults. Handle with care; they will inflict a painful bite when touched.

- Parasitic wasps - Braconid wasps lays eggs inside a hornworm caterpillar, that becomes a living fresh food vessel sustaining the wasp larvae. They exit through a hole they make and spin a cocoon that hangs on the outside of the living worm. If the worm evades the wasp, it becomes a sphinx moth.

- Praying mantis - a strange gangly insect that sits back on its haunches and use its front legs to hold the prey it eats. They will eat anything, even their siblings when they're born; therefore I hold judgment on their being totally a good guy, because they don't discriminate between good guys and bad guys. They can swivel their heads 180 degrees and hold those front legs up like they are praying.

I will enter another group that is not insects, but arachnids - spiders. They feed on a wide variety of insects, capturing their prey in their webs, but here again, good and bad guys get caught up. Even man hates to be caught up in their webs. Beware of the black or brown widow, tarantula, brown recluse that are poisonous to man.

Plants in the carrot family have flowers that attract beneficial predators as well as pollinators. Having a cover crop, like clover, when no produce is growing, helps feed the beneficial insects and keeps them happy.

So bad bug hunters, before you shoot your pesticide pistol at all bugs, research who they are and what their purpose is, then deal with them.

Thank those plants for their air purifying work, taking in the bad air and giving us oxygen.




I am looking for:
News, Blogs & Events Web