IT’S A tuesday morning in new jersey, and you’re waking up and reaching for that cup of coffee when you notice the tomato plants. Yesterday’s lush canopy of green leaves? Now it’s a skeleton of holes and stems. Panic follows, and your first inclination may be: Get out the biggest chemical sprayer I’ve got!
Stop. Look again. Both your conscience and your garden will thank you. Because most caterpillars aren’t some villain determined to wreck your hard work; they’re simply hungry larvae searching for something to eat. Often, all it takes is knowledge to separate guest from pest.
How to Tell Good Caterpillars from Bad Ones
When you spot one of these guys, the visual guide helps break things down into just what it is you’re seeing. It distinguishes between eight hundred moth species and hundred-plus butterfly species that lives here in our state. You’ll understand why that is more important then it seems. For example, moth caterpillars is frequently covered in hair (or spikes or fur) to protect them. Butterfly larvae are usualy plumper and smoother. Knowing how something feels can help you know whether you’ve made a good choice.
A smooth green worm on your fennel or dill? That’s probably a Black Swallowtail larva. You’ll look like you did nothing. But leave it be and get a show later in the summer, one of the most gorgeous butterflies in your yard.
Other guests, however, really are troublemakers. The infographic says this includes destructive creatures like the Corn Earworm (above) and the Spongy Moth. Both can absorbs heavy damage to vegetable gardens and forest trees. Avoid wasting effort on a harmless visitor when there’s a true pest around, and knowing it helps: Can’t ID it? Knowing the difference help prevent you from wasting time protecting a harmless guest while ignoring a real threat.
For instance, are those pale fuzzy caterpillars up high in the trees’ foliage, spinning giant webs at branch tips late-summer? That’s Fall Webworm time. Though they look alarming, they is usually not serious enough to require strong chemicals as long as you catch them early. Again, the key is to know before you spray.
Another big giveaway is host plants. Is it a caterpillar munching on milkweed? More likely than not, it’s a Monarch caterpillar. Its diet makes the creature toxic to would-be predators. This make it something to protect, not eliminate. The iconic migratory butterfly relies on habitat including native milkweed in New Jersey.
It is a spiny green caterpillar with striking white and red bands. That’s an Io Moth larva, perhaps found chomping on your rose bushes or corn. Watch out! Those spines will get you if you’re not careful, and you don’t want to pick up this guy bare-handed.
It is another small, safe detail. A big part of what you’re seeing is timing, too. Fall brings fall Webworms, for example. Spring are when Eastern Tent Caterpillars make their webs in tree crotches. Knowing the seasonal timing makes guessing what comes next easier. You don’t have to spray everywhere, you do things as needed with targeted tactics.
One of the best and most selective controls is hand-picking pests, since you can remove the bad guys but not harm any good guy that happen to come along. It all comes down to balance. In New Jersey, gardening is all about balance, of wanting things to thrive, and wanting things to produce food. You should of tried this sooner.
When you learn to ID these caterpillars, you no longer view each green crawler as the enemy. Instead, you begin to see life cycle for what it is. And if that means sacrificing a few chewed-up leaves now for vibrant butterflies later on (dancing on your deck, later in the season), it’s a sacrifice worth making.