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THE ATTACK OF THE TOMATO HORN WORMS

On or about April 18th 2018, my tomato plants were attacked by an army of Tomato Horn Worms. Over the next 3 days I found over 40 horn worms from 1.5 to over 4 inches in length on my 9 tomato plants that stand 5 feet tall and are loaded with button to baseball sized green tomatoes. The top foot of half of my tomato plants looked like skeletons with leaves missing. I picked the worms off by hand or pruned the leaf they were holding onto and dumped them into a small trailer. They promptly ate all the tomato leaves I put in the trailer. I put the worms later in a plastic container that my wife took over to the Wings Rehabilitation Center to feed to the ducks and other large birds in rehab areas.

On April 20th, I remembered to check the potted tomato plant my wife had me put next to our bedroom patio. Much to my dismay, the plant was mostly a skeleton from which I pulled off 22 Tomato Horn Worms. I found my B.t. (Bacillus thuringienus) worm spray and sprayed all the tomatoes. Spinosad Insect Spray or Take Down Garden Spray would also work.

In my 35 years of gardening, I have never had more than 4 or 5 Tomato Horn Worms on my tomatoes at any one time. They usually attack before the fruit ripens and they will eat the green fruit as well as the leaves and stems. Tomato Horn Worms are the larvae of the Sphinx Moth which is sometimes called the Hummingbird Moth. The many varieties of the Sphinx moth feeds on flower nectar mainly at night, but they lay their eggs on specific plants like tomatoes, potatoes, and tobacco. From the coloration of the worms from green to almost black, I think there were more than one kind of Sphinx Moth laying eggs on the underside of the tomato leaves.

This is an unusual year following the heavy rains and the tree and vegetation destruction of Hurricane Harvey. The trees have grown new leaves on new limbs, and new plants, weeds, and grass have come up thickly and grown tall and fast. I have never seen so many different kinds of caterpillars in my life crawling as well as eating on many different kinds of plants. They are eating wild sunflowers, poke plants, grasses, various weeds which include stinging nettle, plus the leaves on trees. While this area is a major fly way for migrating birds, we don’t seem to have as many birds coming through to eat the caterpillars as in the past. The local population of insect eating birds like the Mockingbird was harmed by the hurricane.

I have pruned the skeleton limbs off my tomatoes and pulled off the partially eaten small tomatoes near the top. This is similar to pruning suckers that grow at the sides of tomato plants and need to be cut both to limit energy going to grow the extra limbs as well as spreading out onto the other row. I hope this pruning by the worms and myself will help the tomatoes grow bigger.

-Herman Green

4/25/2018    Garden Journals