My mother asked me the other day about some shield shaped bugs that were on some of her plants. Being that I live in Charleston, SC and she lives in Raleigh, NC, I was kind of guessing. I am pretty sure they are Stink Bugs, possibly Leaffooted Bugs. After I talked to her, I got thinking about them.....Yes, I have no life, so I think about these bugs and what kind of damage they can do.
I actually have a bunch of these things myself in the yard this year. So, I figured others will too, I might better write about them.
The Brown Stink Bug, Euschistus servus
The Green Stink Bug, Acrosternum hilare
The Leaffooted bug, Leptoglossuis phyllopus
All adult stink bugs are shield-shaped. Green stink bugs are bright green with a narrow orange-yellow line bordering the major body regions. They are about one half inch long. Brown stink bugs are dull grayish-yellow in color and also about one half inch long. Leaffooted bugs are about three quarters of an inch long, have dark brown bodies, and flattened, leaf-like hind legs.
Brown and green stink bugs have been reported as far north as Quebec, however, in the United States, they are more often to inflict more damage to plants in the South.
Stink bugs feed on over 50+ plants, including native and ornamental trees, shrubs, vines, weeds, and many cultivated crops. The preferred hosts are nearly all wild plants. Stink bugs build up on these hosts and move to cultivated hosts as their preferred food becomes unavailable. Among vegetable crops, stink bugs attack bean and cowpea seeds, okra pods, ripening tomato fruit, and stems of melons and asparagus.
Bean, cowpea, eggplant, potato, tomato, peach, strawberry, okra, and watermelon are on the Leaffooted menu as well.
Babies and adults of these bugs pierce plants with their needle-like mouthparts and suck sap from pods, buds, blossoms, and seeds. They use their saliva to penetrate their food material, dissolve the contents and then suck up the digesting mixture. Sorry, but I wanted you to know HOW they do it. The degree of damage depends, to some extent, on the developmental stage of the plant when it is pierced. Immature fruits and pods punctured by bugs become deformed as they develop. Seeds are often flattened and shriveled, and germination is reduced.
Stink bugs overwinter as adults in ditch banks, along fence rows, on roadsides, and in other similar places. They become active in Spring when temperatures rise above 70 degrees. Each female deposits up to several hundred eggs, usually in mid- to late June. These eggs are laid in clusters, primarily on leaves and stems, but also on pods. Approximately 5 weeks elapse between hatching and adulthood. The Leaffooted bug has a very similar life cycle.
Stink bugs have some natural enemies,including several common species of birds, but most notably, parasitic flies in the family Tachinidae. These parasites place their eggs directly on the adults. There are also beneficial stink bugs. Stay with me on this. They can be told apart by their mouthparts. The proboscis or "eating probe" of the beneficial species fold back under the body leaving a space between the body and the mouthparts, whereas in the pest species, the proboscis appear attached to the head at the anterior tip of the head. I have tried to look at the different stink bugs I have around here, I guess they are shy and won't show me their proboscis. OKAY, just to show you I am actually keeping this blog clean, I found this picture of a Spiny Stink Bug, using his proboscis to eat.
They are difficult to control with insecticides, Sevin can be used if the infestation is severe. Please make sure you read and follow the directions! They can be removed by hand, but remember, if held too long or crushed, they emit a foul odor (hence their name). I read of one person, not wanting to take any chances, using a vacuum cleaner to suck them up! Thorough weed control may reduce overwintering populations near fields, but infestation by stink bugs and leaffooted bugs that emerge from nearby woods or other areas is inevitable.
I have often wondered what certain insects are useful for. Bees, we understand are used for pollination. Butterflies are pretty. Spiders eat other insects. Stink bugs, I include leaffooted bugs here, I truly believe are a form of a practical joke. I have been on the recipient end of a good old fashioned stink bomb, I guess Mother Nature wanted to get into the act as well!