June bugs and stink bugs are both common backyard insects across North America, but they belong to entirely different families and cause different problems. June bugs are beetles (scarabs) with rounded, shiny bodies that crash into porch lights on summer nights. Stink bugs are shield-shaped insects known for the foul odor they release when threatened or crushed. Telling them apart is straightforward once you know what to look for.
How They Look
June bugs have a classic beetle shape: oval, convex, and about half an inch to an inch long with a hard, glossy shell that ranges from reddish-brown to dark brown. Their wing covers fit snugly over their abdomen, and they have short, clubbed antennae. They’re clumsy fliers, often bumping into windows and outdoor lights at night.
Stink bugs are flatter and wider, with a distinctive shield or pentagon shape. The brown marmorated stink bug, the most recognizable species in much of the U.S., is roughly the same length as a june bug but looks broader because of its flat body. Stink bugs have long, straight antennae with alternating light and dark bands, and their coloring is a mottled grayish-brown rather than the june bug’s glossy finish. Their wings fold flat across their backs, giving them a very different silhouette from a rounded beetle.
The Stink Bug’s Signature Smell
The most obvious behavioral difference is odor. Stink bugs earn their name by releasing a chemical secretion from glands on their thorax when disturbed. This defensive spray contains a mix of long-chain alkanes, aldehydes, and esters that produces a sharp, unpleasant smell often compared to cilantro or burnt rubber. Crushing or vacuuming a stink bug will release this odor, though contrary to popular belief, the smell does not attract other stink bugs into your home.
June bugs have no comparable defense mechanism. They don’t bite, sting, or produce any notable odor. Their main survival strategy is their hard exoskeleton and their tendency to be active at night when fewer predators are hunting visually.
What They Eat and Damage
These two insects cause entirely different kinds of damage, which matters if you’re trying to figure out what’s hurting your yard or garden.
June bug adults feed on tree and shrub foliage but rarely cause serious harm. The real damage comes from their larvae: white, C-shaped grubs that live in the soil and feed on grass roots. These grubs range from half an inch to an inch and a half long, with six legs, a brown head, and visible mouthparts. A grub infestation shows up as thinning or dead patches of turf, and the grass pulls up easily because the root system has been eaten away. Skunks and raccoons digging up your lawn at night is often the first sign of a grub problem, since they’re hunting for the large, protein-rich larvae. June beetle grubs take two to three years to fully develop in the soil, making them a persistent problem. Damage typically appears between March and October and is most common in non-irrigated lawns.
Stink bugs are above-ground feeders. They use piercing mouthparts to suck juices from fruits, vegetables, and ornamental plants. The brown marmorated stink bug feeds on upwards of 60 plant species, including tomatoes, peppers, apples, peaches, and soybeans. Their feeding leaves dimpled, discolored spots on fruit and can cause significant crop losses. In years with heavy spring rain and late weed growth, stink bug populations can surge and cause more widespread garden damage.
When and Where You’ll See Them
June bugs are a summer insect. Adults emerge from the soil in late May through June (hence the name), mate, and lay eggs in the ground. They’re almost exclusively nocturnal and are strongly attracted to artificial light, which is why they cluster around porch lights and street lamps. You’ll rarely encounter a june bug indoors unless one flies through an open door at night.
Stink bugs have a longer active season. They overwinter on the ground in leaf litter and become active in late winter or early spring. They feed and reproduce through summer, laying clusters of barrel-shaped eggs on the undersides of leaves. Their life cycle moves through five nymph stages before reaching adulthood, with the nymphs gradually developing wing pads at each stage. In fall, stink bugs become a household nuisance because they seek warm shelter to overwinter, squeezing through cracks in foundations, gaps around windows, and other small openings. This is when most people discover them indoors, sometimes in large numbers.
The Invasive Species Factor
Most june bug species are native to North America and are a normal part of the ecosystem, even when their grubs damage lawns.
The brown marmorated stink bug is a different story. Native to eastern Asia (China, Japan, and Taiwan), it was first documented in the U.S. in Pennsylvania in 2001, though it likely established as early as 1996. It has since spread to at least 15 states with confirmed populations and has been found occasionally in more than a dozen additional states. It was first detected on the West Coast in Oregon in 2004. Its wide host range and lack of natural predators in North America make it a significant agricultural pest, particularly in the Mid-Atlantic states where it has caused millions of dollars in crop damage.
Safety for People and Pets
Neither insect poses a real danger to humans. June bugs don’t bite or sting. Stink bugs don’t bite either, though their odor is certainly unpleasant.
Pets, especially dogs and cats, often try to eat both insects. June bugs are not toxic, though eating several can cause mild stomach upset. Stink bugs are also not poisonous, but their chemical secretions irritate the gastrointestinal tract. A dog or cat that bites into a stink bug may drool excessively or vomit, and the secretions can irritate the tongue, gums, lips, and inner cheeks. These symptoms are short-lived and don’t cause long-term health effects.
How to Manage Each Pest
Because they cause different problems, june bugs and stink bugs call for different control strategies.
June Bug Grubs
Grub control focuses on the lawn. If you’re finding dead turf patches that peel back like carpet, check for white grubs in the top few inches of soil. Keeping your lawn well-irrigated actually helps, since june beetle grubs and their damage are uncommon in irrigated turf. For active infestations, soil-applied grub treatments work best when timed to target young larvae in late summer or early fall, before they grow large and burrow deeper for winter.
Stink Bugs
Stink bug management is largely about exclusion. Seal gaps around windows, doors, and foundation cracks to prevent them from entering your home in fall. If they get inside, remove them by hand or with a vacuum, keeping in mind that crushing them releases their odor. A simple homemade trap works well: fill a roasting pan with soapy water, place it in a dark room, and shine a light toward it. Stink bugs are attracted to the light and drown in the water.
Indoor pesticide treatments are generally ineffective against stink bugs. If you choose a chemical approach, correctly timed outdoor perimeter treatments applied before they move inside in fall offer the best results. In the garden, hand-picking stink bugs off plants in the morning when they’re sluggish is a practical first step, and row covers can protect vulnerable crops during peak season.