They're gone

Forgive the lack of photo on this post, but there's a good reason. Remember those io moth caterpillars that I said were disappearing?. Indeed, they're gone (hence the lack of photo). They didn't seem large enough to be ready to pupate, but who knows. Or maybe one of those huge crows that haunts our office gobbled them up. Who knows. I guess that's the way nature works.

They're baaaack!

It looks like we've got a fresh crop of io moth caterpillars on one of the redbud trees outside the office. Jen noticed them last night as she was leaving work. This time they're on the opposite tree from the last group of io caterpillars that were here in August.

I watched them for a little bit this morning. There are nine of them this time, and they're all clumped on a single branch. Funny. I wonder if they like to be around their brothers and sisters. I think they'll have to pick a new branch soon -- the one they're on is darn near defoliated.

It will be interesting to see how long this batch stays before they disappear. The last batch was around for maybe two weeks before they all vanished. I assume they pupated, but I never did see any coccoons, apparently because they leave the host plant in order to pupate.

Io moth caterpillars

Io moth caterpillars
Originally uploaded by sassycrafter

While walking in from lunch yesterday, I noticed that the 'Forest Pansy' redbud at our office had some serious munch marks. I flipped over the leaves and, lo and behold, there were several io moth caterpillars hiding out.

I just love the color of these caterpillars--almost an electric lemon-lime color--so I like to get close and really admire them. But it's best not to touch--they have stinging spines on their bodies (see the tufts?), so it's a good idea not to touch them.

Caterpillars typically go through several stages before pupating and turning into moths or butterflies. These caterpillars are probably first instars, based on their markings. In time, they'll develop into io moths.

Scout early and often

Tomato hornworm caterpillar on my tomato plant
Originally uploaded by sassycrafter

I've been checking my tomato plants almost daily to see how they're progressing (lots of baby tomatoes!) and also to check for signs of diseases and pests. This week I found my first tomato hornworm caterpiillar.

Well, to be truthful, I found the frass first. Frass, you ask? Well, it's just a fancy word for caterpillar poop. It's usually easy to spot because it's dark and stands out strongly against the leaves, unlike the caterpillars themselves which tend to blend in. For a close-up of the frass, click here.

I scoured the tomato bushes and found four young caterpillars and quickly introduced them to the bottom of my shoe. This is the first line of defense (pick and squash) if you're using integrated pest management. My next step was going to be treating the plants with Bacillus thuringiensis, a microbial insecticide, but I was unable to purchase it at my local big box store during last night's late shopping trip. Darn those big box stores.

My tomatoes have shown other signs of pest damage, namely leaf miners, but I haven't treated them because leaf miners usually don't cause major problems. Tomato hornworms, on the other hand, have voracious appetities. No way I'm leaving those buggers on my prized tomatoes.

Update 6/21/08: it looks like I misidentified this caterpillar. It's actually a tobacco hornworm (Manduca sexta) and not a tomato hornworm (Manduca quinquemaculata). Tomato hornworms have eight white V-shaped markings on their side while tobacco hornworms have seven diagonal white lines.