Subject: Tomato caterpillars
Geographic location of the bug: St. Elizabeth, Jamaica
Date: 04/09/2018
Time: 09:04 AM EDT
Your letter to the bugman: Hello Bugman!
I’ve been enjoying your website for years and I am now excited to submit my first question! I am a Peace Corps volunteer serving in Jamaica and my host father is growing some of the most beautiful tomatoes in the entire world. However there is an aggressive caterpillar pest Wreaking havoc on his produce. I am trying to encourage less toxic methods to deal with such pests in the community and I was hoping that you could identify the species of caterpillar for me in order to create a more targeted management method. Thank you so much for your help and keep up the good work!
How you want your letter signed: Farming PCV
Dear Farming PCV,
This is some species of Cutworm in the family Noctuidae, and many caterpillars in the family look very similar. Our internet search did turn up images on Minden Pictures of the Caterpillar of the Large Yellow Underwing, Noctua pronuba, feeding on the leaves of a tomato plant, and BugGuide states “Larvae feed on a variety of crops and vegetables, plus grasses”, but even though we see a similarity, we do not believe that is your species. We found an image on Colourbox that is identified as a Turnip Moth cutworm, Agrotis segetum, eating a tomato, and it resembles your culprit, but other images of this caterpillar we located on the internet are brown and we cannot confirm that identification either. Both species we have mentioned are Old World species, but the Large Yellow Underwing has been introduced to North America. We found additional images of brown Cutworms eating tomatoes on Dreamstime and then we believe we found your culprit on Alamy where it is identified as a “Bright-line Brown-eye moth, also known as tomato moth (Lacanobia oleracea).” According to UK Moths: “Favouring suburban habitats as well as salt-marshes, the larval foodplants in the wild are usually orache (Atriplex) and goosefoot (Chenopodium), but it can sometimes attack cultivated tomatoes, feeding internally in the fruit.” Wikipedia does not list Jamaica nor any other New World location, but that does not mean the species has not been introduced. It might just be undocumented at this time. Wildlife Insight offers the following advice: “To prevent the adult moths from laying eggs on the plants some fine mesh should be placed over the greenhouse windows between May and August. Doors left open during the day to allow bees to enter should be netted off if left open at night. If growing tomatoes outdoors then the whole plant will have be cloaked in netting. Any clusters of eggs are usually easy to find on the underside of the leaves and can then be scrapped off. At the first sign of fenestrations appearing in tomato leaves check the undersides for the tiny caterpillars. The location of the feeding caterpillars is often given away by fine dark freckling of frass on the leaves directly beneath those being eaten.”
Thank you so very much for your assistance!