Stink bugs are shield-shaped bugs with a large scutellum or triangle on their backs. Most bugs are brown
or green with red, pink, or yellow markings.
Two of the most common pests in California gardens are the consperse stink bug, Euschistus conspersus, and the harlequin bug, Murgantia histrionica. Coloration in bugs varies. The consperse stink bug, Euschistus conspersus, is usually gray brown to green with speckled black legs. Don't confuse the consperse stink bug with the rough stink bug, Brochymena sulcata, which is a predator. The brown marmorated stink bug, often confused with the rough stink bug or consperse stink bug, is an invasive species and serious pest of many fruit and fruiting vegetable crops. The harlequin bug is black with distinctive red markings. Harlequin bugs can be confused with Bagrada bugs, an invasive species, but are much larger and lack the white markings characteristic of Bagrada bugs. Two other common stink bug species are the Say stink bug, Chlorochroa sayi, and the southern green stink bug, Nezara viridula. The Say stink bug is green with a white rim around its borders. The southern green stink bug is bright green and larger than other stink bugs. Consperse stink bug is the dominant species found in fruit and nut trees; the others are found primarily in vegetables.
Drum-shaped eggs with circular "lids" are laid in clusters on foliage. The nymphs, nearly round and often brightly colored, remain close together at first but scatter as they grow. They pass through four or five molts, gradually developing wings and adult coloration. Adults overwinter on the ground under leaves and become active in March or April. Stink bug infestations originate when adults fly in from weedy areas, often from the edges of sloughs and creeks where blackberries grow. Damage is often limited to the edges of fields near these areas, but in years with a lot of spring rain and late weed growth, stink bugs may be numerous and damage more widespread.
Stink bugs attack a variety of fruits and vegetables from stone fruits to pears to beans to tomatoes,
often leaving blemishes, depressions, or brown drops of excrement. On green tomatoes, damage appears as
dark pinpricks surrounded by a light discolored area that remains green or turns yellow when fruit ripen.
Areas beneath spots on tomatoes or depressed areas on pears become white and pithy but remain firm as
the fruit ripens. On peaches, fruit turns brown and corky.
Handpick bugs or their eggs. Eliminate groundcovers or weedy areas in early spring before populations
build up. Insecticides are generally not recommended in gardens for stink bugs. Parasites and general
predators may contribute to control.
See also True Bugs for more information.
Consperse stink bug adult
Eggs and nymphs of consperse stink bug
Damage to tomato
Damage to apple