August 20, 2012

Going buggy in the garden

By AMY IVY, Cornell Cooperative Extension

---- — This has been a banner year for bugs in the garden. 

Some of them help us out by pollinating our crops or serving as food for bluebirds and swallows, and some prey on other bugs that are harmful. But the bugs that get gardeners’ attention the most are the bad bugs — those that damage our crops and plants.


In just the past couple of weeks we’ve seen a population explosion in green stink bugs. 

Every year, we can expect a good number of brown stink bugs — and some green stink bugs — to cause damage to vegetable and fruit crops (especially tomatoes). But, this year, we’re seeing green stink bugs in unusually high numbers. 

The immature stages tend to hang out on your plants in masses. They can be a real nuisance and do quite a bit of damage, especially to your developing tomato fruits. Knock them off with a strong spray of water, or call our office for something stronger to use. 

This website has more information on the pests as well as excellent pictures of all their life stages:


We’ve also been getting a lot of calls and questions about what is happening to the black locust trees around Plattsburgh. I see a lot of them from the Northway, around exits 36 and 37. These tall trees are completely brown right now, so it’s easy to identify them among their unaffected, green neighbors of other species. 

These black locust trees are attacked every year by the locust leafminer. The larva of this pest tunnels between the layers of the leaf, which is where it gets its name. The adult feeds on the leaves as well, turning the leaves completely brown and dead by early to mid-August. 

Surprisingly, the trees leaf back out again the following spring as if nothing happened. It must be because the damage occurs late enough in the summer that the trees can afford to lose their leaves. These beetles feed only on black locusts, so you don’t have to worry about them attacking any other type of tree.


In my vegetable garden I’ve been struggling with what to do with the tomato hornworms that are devouring my gorgeous tomato plants. These are huge caterpillars, as thick as my thumb and up to 4 inches long, so they can really do some damage. 

The hard part is that they turn into really interesting hummingbird moths (they’re also called sphinx moths and clear-winged moths). The adult moths get this name from the way they fly around and drink the nectar of flowers, just like a hummingbird. Although the caterpillar of this creature devours my tomatoes, I try to co-exist with it as much as possible so it can turn into that fascinating adult.

For more information and to see some great photos of this insect, visit 


Another beautiful bug that deserves attention is the argiope spider, also called the garden spider. I spotted one in my mugo pine just this morning. 

This good-sized yellow and black spider makes a beautiful, large orb-type of web, much like Charlotte the spider made in “Charlotte’s Web.” The argiope adds a showy, white zig-zag right down the middle of the web and usually rests head down, in the very center, waiting for something to become entangled. 

Leave this beautiful creature alone and let it do its job of dispatching with many of those annoying flies in your yard. 

As always, if you’re in doubt about the identity of a bug in your yard, garden or home, drop off a sample at any Cornell Cooperative Extension office.

Amy Ivy is executive director of Cornell Cooperative Extension, Clinton County. Office phone numbers: Clinton County, 561-7450; Essex County, 962-4810; Franklin County, 483-7403. Website: Email questions to