# Rose chafer (Macrodactylus subspinosus) > A small, tan-golden scarab beetle that feeds on flowers and foliage of roses, grapes and many garden plants, active in late spring and early summer. Source: https://insectscanner.com/species/rose-chafer/ (updated 2026-10-10) ## Is it dangerous? **Non-toxic.** Rose chafers do not have venom and are not dangerous. They do not sting; they may nibble if handled but bites are rare and harmless. Wash hands if you handle many beetles. **Pets:** Not known to be a problem for cats or dogs, though eating many could cause a mild stomach upset. Rose chafers contain a toxin that can be fatal to chickens and other small birds that eat them, so keep backyard poultry and pet birds away from heavy infestations. Contact a veterinarian if an animal becomes unwell after eating them. ## Quick facts - Scientific name: Macrodactylus subspinosus - Also called: Rose bug - Order: Coleoptera (Beetles) - Family: Scarabaeidae (Scarab beetles) - Size: 7-11 mm long - Colours: Golden tan, Light bronze, Brown (legs/underside) - Habitat: Open habitats: gardens, lawns, vineyards, orchards, fields and hedgerows where host plants (roses, grapevines, fruit trees, ornamental shrubs) are present. - Range: Eastern and central North America, extending from parts of Canada south through the United States. - Active: Late spring to early summer (commonly May to July); diurnal (active in daylight). - Lifespan: Adults live about 3-6 weeks; full life cycle takes about one year (one generation per year). - Effect on plants: Foliage and flower feeder - Pest: yes ## Overview Macrodactylus subspinosus is a common North American chafer beetle notable for feeding in groups on blossoms and foliage. Adults are most conspicuous in late spring and early summer when they fly awkwardly to and from host plants. Larvae are C-shaped white grubs that develop in soil and feed on grass and plant roots. Populations can cause noticeable cosmetic and crop damage in gardens, vineyards and orchards but are not dangerous to people. ## How to identify it Adults are slender, somewhat elongate scarab beetles with long legs and antennae ending in small lamellate clubs. Their overall colour is a straw-golden to tan or light bronze with fine hairs and sometimes a faint metallic sheen. The legs and undersides are slightly darker. Larvae are typical white, C-shaped scarab grubs with brown heads, found in soil. - Size about 7-11 mm, slender, straw-golden to light bronze body with fine hairs. - Long legs and slightly clubbed antennae typical of chafer beetles. - Active in daytime on flowers and leaves in late spring to early summer; often seen in groups. - Larvae are white, C-shaped grubs in soil near roots. ## Lookalikes - **Japanese beetle** (Popillia japonica): Japanese beetle is smaller to similar size but has metallic green head and coppery wing covers and a distinct row of white tufts along the sides; rose chafer is uniformly tan/golden. - **Grapevine beetle** (Pelidnota punctata): Grapevine beetle is larger (often 20-30 mm) and more orange; rose chafer is much smaller and more straw-colored. ## Life cycle - **Egg:** Females lay eggs in soil, often in sandy grassy areas, in early to mid summer shortly after mating; eggs hatch in one to three weeks depending on temperature. - **Larva (white grub):** Larvae are C-shaped white grubs that feed on grass and plant roots in soil through summer and fall, then overwinter in the soil. - **Pupa:** Larvae pupate in soil in spring as temperatures warm, developing into adults. - **Adult (beetle):** Adults emerge in late spring and early summer, feed on flowers and foliage for several weeks, mate and the females lay eggs in soil. ## Diet and predators - Young eat: Roots and organic matter in soil (grass roots, seedlings). - Adults eat: Flowers, petals, leaves and soft fruit of roses, grapes, fruit trees and many ornamentals. - Predators of the young: Ground beetles, small mammals, parasitic nematodes and entomopathogenic fungi. - Predators of adults: Predatory insects, spiders and some parasitic flies or wasps; many birds avoid them because the beetles contain a toxin harmful to birds. ## Effect on plants and gardens Adults feed on blossoms, leaves and fruit of roses, grapevines, cherries, apples, raspberries and many ornamentals. Feeding often skeletonizes leaves or strips petals; larvae feed on grass roots and can damage lawns and seedlings. ### How to get rid of it Handpick adults into soapy water early in the day, and cover valuable plants with fine netting or floating row covers during the few weeks of adult activity. Grubs prefer light, sandy soils, so maintaining dense turf and improving sandy areas can reduce breeding. In severe cases on fruit or ornamentals, use insecticides labeled for rose chafer, following label directions and avoiding spraying open blooms visited by bees. Traps are generally not recommended because they can attract more beetles. ## Where and when to find it Adults on open flowers, rose blooms, grape leaves and fruit tree foliage; larvae in soil feeding on grass and roots. - Best time: May to July, during warm sunny days; early to mid-afternoon is often best for observing adults. - Tips: Photograph them on flowers at close range; sweep-netting over roses and grapevines will catch adults. To spot larvae, inspect soil in lawns or near plant roots in late summer and spring. ## Fun facts - Rose chafers often feed in groups and can quickly strip blooms, giving them a reputation as garden pests. - Despite their name, they feed on many plants besides roses, including grapes, fruit trees and ornamentals. - Adults are clumsy fliers and are most noticeable during warm, sunny days when they hop between flowers. ## Frequently asked questions ### Are rose chafers dangerous to people? No. They do not sting or carry diseases harmful to people. Handling may cause some nibbling but bites are rare and harmless. ### Do rose chafers bite? They are not known for biting people; any bite would be accidental and minor. ### Why are rose chafers in my garden? Adults are attracted to flowers and tender foliage. Gardens with roses, grapevines or fruit trees provide food and are common feeding sites. ### How do I get rid of rose chafers? Handpick adults into soapy water, use fine netting or floating row covers over susceptible plants during peak activity, encourage birds and beneficial insects, and maintain healthy turf to reduce grub damage. In severe cases, targeted insecticides or biological controls (nematodes) can be used following label instructions. ### Do rose chafer larvae damage lawns? Yes, larvae feed on grass roots and can damage lawns and seedlings if present in high numbers, though damage is usually patchy. ### When are rose chafers most active? Late spring to early summer (commonly May to July), during warm, sunny daytime hours. --- More about this species: [iNaturalist](https://www.inaturalist.org/taxa/130504), [Wikipedia](https://en.wikipedia.org/wiki/Macrodactylus_subspinosus). Identify insects and spiders from a photo with the Insect Scanner iPhone app: https://apps.apple.com/app/id1543946563?pt=126685406&ct=web-markdown&mt=8 Identification from photos is never certain: don't handle insects you can't identify, and get medical advice for bites, stings or allergic reactions.