by Deborah Foster
Being a Virginia native, my first encounter with a Georgia Thumper didn't occur until I moved to Milledgeville and took a job at Lockerly Arboretum. Some visitors are intrigued while others are startled by this large, odd looking grasshopper commonly called the Eastern lubber (Romalea microptera).
The Eastern lubber grasshopper is limited to the southeastern region of the United States. It is found from North Carolina south through South Carolina, Georgia and Florida, and west through Alabama, Mississippi, and Louisiana to central Texas.
Lubbers are defoliators, consuming the leaf tissue of plants. They climb readily, and because they are gregarious they can completely strip foliage from citrus trees, vegetable crops and landscape ornamentals. Last summer lubbers got into the greenhouse at Lockerly and helped themselves to some of the orchids. Young lubbers usually travel in large numbers, swarming and devouring plant material as they go.
Unlike other grasshoppers who can jump and fly, the Eastern lubber is quite clumsy and slow in movement and mostly travels by walking and crawling feebly over plants. "Lubber" may seem like a strange name for a grasshopper but it actually is a good fit. "Lubber" is derived from an old English word "lobre" which means lazy or clumsy. Seafarers often use the word "landlubber" to describe a person unfamiliar with the sea or sailing.
Adult lubbers are usually 2.5 to 3 inches long. Adults are usually a dull mustard yellow with
various black spots and markings, but their coloration varies widely and darker forms also exist. The immature Eastern lubber differs dramatically in appearance from the adults. They are almost completely black, with a bright yellow, orange, or red stripe down the back.
The bright colors and patterns on a lubber's shell is a warning to predators that they are unpalatable and maybe even poisonous. Lubbers ingest substances in the plants they consume that are toxic to many predators. These chemicals can kill smaller creatures like birds and lizards or leave larger animals quite ill after ingesting a lubber. Because of their poisonous nature, the Eastern lubber has very few predators to fear. There are however, a few clever creatures in nature that have found ways to conquer the lubber. The Tachinid fly is a large family of parasitoid flies that lay their eggs in other insects. The fly eggs hatch and feed on the host insect, eventually killing it. Tomato hornworms can suffer a similar fate from the activity of a braconid wasp. You may have seen hornworms in your garden with white wasp eggs on their backs.
Another predator that helps control lubber populations is a small bird called a loggerhead shrike. Loggerhead shrikes (Lanius ludovicianus) are predatory songbirds that prey on insects, lizards, and small mammals. They are gray with a black mask and black and white wings. Shrikes are famous for impaling larger prey on thorns or barbed wire fences to be eaten later, which is perfect for preparing lubbers. After 1 or 2 days, the toxins degrade and the dead lubbers become edible.
When only a few of these pests are present, they are easily controlled by hand removal. They are easy to catch because they move so slowly. How you dispose of them is a matter of personal preference. Smashing them can get a little messy so I prefer to toss them into a bucket of soapy water. This method also works well with Japanese beetles. Just place the bucket of soapy water under the leaf or stem where the beetles have congregated and give the plant a good smack. The beetles will drop off into the bucket and stay there. I usually let the bucket set for a few hours to ensure their demise, returning later to pour them out.
If hand-picking isn't an option, insecticides can be applied to either the foliage or directly to the grasshopper. Insecticide treatment is most effective for young grasshoppers. Insecticides that will kill lubbers include carbaryl, bifenthrin, permethrin and spinosad. Baits with insecticide are sometimes formulated for grasshopper control and are sprinkled on the soil surface near the plants being protected.
Lubbers over-winter in the egg stage. The female deposits a large number of eggs in the soil at a depth of 1 to 2 inches and closes the hole with a frothy secretion. The eggs will remain in the soil through late fall and winter and then begin hatching in the spring. The young grasshoppers crawl up out of the soil upon hatching and congregate near suitable food sources. Lubbers may be found from March to about November.
If you have never seen an Eastern lubber, come on out to Lockerly and we will be happy to show you. Lockerly is open Monday through Friday from 8:30 to 4:30 and on Saturday from 9:00 to 1:00.