The Stink Bug is also known as a shield bug because of the shield-like shape of its body. It also gets its name from the pungent odor it emits when squashed, jostled, cornered, scared or injured. In large groups, stink bugs are considered agricultural pests because they suck juices from their host plants and cause damage to crops.
The stink bug gets its family name, Pentatomidae, from its five-segmented antennae. It also has a segmented beak and three body segments. Nymphs are similar to adults but smaller and without wings. Stink bug nymphs also have stink glands.
There are several species of the stink bug that are considered to be pests:
Brown Marmorated Stink Bug. Southern Green Stink Bug. Forest Bug. Harlequin Bug and the Rice Stink Bug.
Four species of stink bugs are considered to be beneficial instead of pests:
The Anchor Bug preys upon the Mexican bean beetle, Japanese beetle and other insects; the Two Spotted Stink Bug preys upon Colorado beetle larvae; the Spined Soldier bug feeds on caterpillars and other slow moving arthropods; the Arboreal Stink Bug patrols tree trunks for ants and insects.
The Stink Bug is part of the order Hemiptera considered “true bugs” and are related to cicadas, aphids and plant hoppers because they all share common sucking mouthparts and wings that are covered with a membrane.
Since the stink bug is also known as a shield bug, the following descriptions are of stink bugs and shield bugs that are considered to be pests.
Native to China, Japan, Korea and Taiwan, the Brown Marmorated Stink Bug was introduced several years ago in the United States. It is currently found in Oregon, Pennsylvania, New Jersey, Maryland, West Virginia and Louisiana. The Brown Marmorated Stink Bug is identified by shades of brown on its shield shaped body. It also has lighter colors on its antennae and dark colors on its lower wings which distinguished it from other stink bugs. Like other stink bugs, it has scent glands located on its abdomen that produces a foul smelly liquid.
Adult Brown Marmorated Stink Bugs mate in early spring and females lay a mass of eggs weekly under the leaves of the host plant. She can lay up to 400 eggs in her lifetime. Eggs are light yellow to yellowish red. Nymphs are tick-like in appearance. They go through five nymphal instars before becoming adults and have red
eyes and an abdomen that changes color during each of the instars.
As a pest, the Brown Marmorated Stink Bug will attack apples, cherries, raspberries, peaches, figs, mulberries, citrus fruits and persimmons. Feeding on fruit trees causes “cat facing” which will damage the fruit. They have also been found on ornamental plants, weeds, soybeans and green beans. The Brown Marmorated Stink Bug will over winter in homes entering through small openings in windows and door frames, under roof shingles, in crawl spaces and attics.
The bugs will hibernate until winter passes and sometimes the warmth of the building they live in will cause them to become active. They will fly clumsily around light fixtures and leave a scent on anything they land on. Their odor is the reason they return year after year to the same place to hibernate. This odor is a beacon for other stinkbugs that that particular location is a good hibernation nest.
The Southern Green stink Bug originated in Ethiopia and is currently found in Europe, Asia, Africa and North and South America. In the United States they are found in Florida, Georgia, Alabama, Mississippi, Louisiana, Texas, Virginia, California and Hawaii. They are active from October to December and March to April.
Adult Southern Green Stink Bugs are shield shaped and have red or black eyes and a green color. They also
have black dots on the sides of their abdomen. After mating, females lay eggs under leaves of crops and weeds such as the beggar weed, rattlebox weed, Mexican clover and wild blackberry nut grass. Females can lay 260 eggs during a lifetime and produce four generations per year in warm climates.
Nymphs are light yellow with red eyes and transparent legs and antennae. They go through five instars before becoming adults. After hatching, nymphs remain near the eggs until they go through the second instars during which time they begin feeding and their legs and thorax turn black. Their abdomen is red with a yellow spot on each side.
During the third and fourth instars, they grow in size, turn greenish in color and have some color on their wings.
Their abdomen is yellowish green with red spots. The fifth instar lasts eight days before they become adults.
As a pest, the Southern Green Stink Bug feeds on growing shoots and developing fruits. Infected shoots wither and die and fruit show brownish or black spots that affects the fruits quality. Young infected fruit wilts and drops from the
plant. The Southern Green Stink Bug can fall prey to the Tachinid fly in Florida that parasitizes adults and nymphs and wasps that parasitized the eggs.
Found in forests and woodlands worldwide, the Forest Bug is identified by its shiny brown color and its reddish orange markings on its body. It has orange legs and plates that extend forward from its shield shaped body.
The Forest Bug feeds on several species of oak trees. Mainly a sap feeder, it has piercing mouthparts and is also found on other deciduous trees. Considered an agricultural and garden pest, the Forest bug will feed on fruit and nut trees and occasionally on other insects. Like other stink bugs, the forest bug has scent glands that emit a foul odor. Females lay their eggs during the summer in the cracks of tree bark.
The Harlequin Bug is a stink bug that is identified by it red and black spotted colors and long, flat, shield-shaped body. They are pests of cabbage, cauliflower, turnips, horseradish, collards, mustard, Brussels sprouts, tomato,
potato, egg plant, okra, beans, asparagus, beets, weeds, fruit trees and field crops. They are found in the southern half of the United States and rarely found north of Colorado and Pennsylvania.
The Harlequin Bug, like other stink bugs, sucks plant juices from plants and causes the host plant to wilt brown and
die. In large groups they are able to destroy entire crops when not controlled.
There are three stages of the Harlequin Bug: egg, nymph and adult.
Nymphs go through five to six instars before becoming adults. They transition from pale orange to black with their antennae being colorless as a nymph and darkening to black as an adult. Eggs are tiny white kegs that stand on double rows on the undersides of plants. Each egg is marked with two black hoops and a black spot.
Harlequin Bugs over winter in cabbage stalks, bunches of grass and other rubbish.
The Rice Stink Bug is found east of the Rocky Mountains up to southern Minnesota and New York and into the southeastern states. They are also found in the Northern Gulf Coast of Mexico and the West Indies.
The Rice Stink Bug is a pest of grasses, sorghum and rice. During the winter months (October to April) they
over winter in wild grasses and come spring they migrate from wild grasses to sorghum and rice fields when plants start developing their kernels.
Rice Stink Bugs feed on rice during the soft dough stages which leaves an empty seed coat. When feeding they secrete salivary enzymes that harden on contact with air and remains attached to the rice grain. This is the only evidence on the rice stalk that the bug was there.
The Rice Stink Bug is identified by its golden brown color. They are 1/2 inches long and have forward pointing spines on their shield-like bodies. Nymphs are bright red with black markings. During the spring, females lay eggs in double rows on leaves and seeds of wild grasses, sorghum and rice. Nymphs molt five times over 28 days before becoming adults.
Our thanks to Lani Powell for research and writing which made this information page possible!