Brown Marmorated Stinkbug

Halyomorpha halys

Appearance

• Adults are approximately 17 mm (5/8 inch) long
• Mottled brownish grey color
• They are the typical “shield” shape

Lifecycle

• Adults emerge from their overwintering sites in the spring, usually in early May. After they feed for about two weeks, they mate, and the females begin to lay eggs. 
• Eggs are pale green, elliptical-shaped, laid in clusters of 20-30 eggs on the undersides of leaves from June to August. 
• A single female can lay up to 400 eggs. Eggs hatch in three to seven days.
• Nymphs range in size from 2.4 mm 1st instar nymphs to 12 mm 5th instar nymph.
• Dark red eyes; abdomen yellowish-red in 1st instar, off-white with reddish spots on abdomen of later instars
• The nymphs pass through five instars (sub-stages), with a molt between each instar. Each instar lasts about one week, before the final molt into the adult stage. 
• New adults start to appear in late July or August. 
• Adults - 17 mm long, shield-shaped, and have a mottled appearance of brown and grey colors. Alternating dark & light colored bands on the last two segments of the antenna and exposed edges of abdomen.
• There is one generation per year in the mid-Atlantic region.

The stink bug is also a prolific breeder, producing up to two generations each year. In warmer climates, it’s known to reproduce up to six times a year. Each female can lay up to 400 eggs in her lifetime.

Habits

• When handled or crushed, stink bugs release a foul smelling secretion from glands on the top side of the thorax & underside of the abdomen.
• What do stink bugs eat? They feed on plants by piercing fruits and stems. Known food sources include: pear, peach, apricot, cherry, mulberry, persimmon, and apple trees; Buddleia, honeysuckle, Rosa rugosa, and abelia shrubs; raspberries and grapes; and legumes including soybeans and beans.