A small metallic green and copper beetle is now drawing close attention from plant-health services in France. During summer 2026, several Japanese beetles, or Popillia japonica, were caught in the Doubs and Côte-d’Or departments, in Strasbourg and in the Alpes-Maritimes. These findings do not mean that a lasting population has been established at every site where a trap caught an insect. They do show that the beetle can arrive along several transport routes and that early detection matters.

For gardeners, orchard growers, winegrowers and nurseries, the right response is neither panic nor improvised spraying. It is to observe, capture when this can be done simply, and report quickly. The Japanese beetle is a priority quarantine pest in the European Union. A well-documented sighting can help the authorities determine whether an insect is an isolated hitchhiker or an early sign of a breeding population.

What happened in France during summer 2026?

The European and Mediterranean Plant Protection Organization, or EPPO, compiled findings reported by France’s national plant-protection authority. The first specimen of 2026 was caught on 16 June at a site near the A36 motorway in the Doubs. Another adult was found on 7 July at a motorway service area in Côte-d’Or. The Bourgogne-Franche-Comté regional agriculture authority says both identifications were confirmed by the French national reference laboratory at ANSES.

In Grand Est, one adult was caught in Strasbourg on 26 June and a second near the first location on 1 July. In the Alpes-Maritimes, one male and one female were found on 18 June in an orchard near a major transport route. Five more adults were then caught near a golf course in early July. On 17 July, the Provence-Alpes-Côte d’Azur regional authority confirmed a further detection at Mougins.

Adding the captures detailed by EPPO gives at least eleven adults in 2026 across three French regions. The key word is still “capture”. EPPO officially describes the pest status in France as transient, actionable and under eradication. Authorities have found insects and intensified surveillance, but those facts alone do not demonstrate a self-sustaining population at each detection site.

Why is the Japanese beetle monitored so closely?

The Japanese beetle is polyphagous, meaning it can feed on a very wide range of plants. The French agriculture ministry’s current factsheet lists more than 300 food, forest and ornamental plant species. Grapevines, several fruit trees, maize, beans, roses and lawns are among the hosts under surveillance.

Damage differs with the insect’s life stage. Adults consume leaves, flowers and sometimes fruit surfaces. In large groups, they can leave only the veins of a leaf. The larvae live in soil and feed on roots, especially grass roots. That two-part life cycle is why monitoring covers crops and gardens as well as some regularly maintained lawns.

Its regulated status does not mean that every shiny green beetle is a threat. France has many native chafers and flower chafers that are harmless or useful and are not quarantine pests. Accurate identification prevents people from killing those species by mistake while allowing credible cases to reach specialists quickly.

How can you identify Popillia japonica?

An adult is about 10 to 12 millimetres long. Its head and thorax are metallic green, while the hardened wing covers are copper-brown. Colour is not enough for identification: several European beetles can look green or bronze as the light changes.

The most useful feature is on the abdomen. The French ministry describes five tufts of white hair along each side, plus two larger white tufts at the rear. Try to take a sharp photograph from above and, if possible, another from the side.

  • Size: roughly one centimetre, smaller than many familiar large chafers.
  • Colours: metallic green forebody and copper-coloured wing covers.
  • Key mark: ten small white side tufts and two larger rear tufts.
  • Behaviour: adults may gather to feed on leaves, flowers or fruit.

A photograph cannot replace expert confirmation. Lighting, angle or damage to the insect can hide the white tufts. Conversely, a native garden chafer or rose chafer may look similar in a distant image. If the main features appear to match, sending a report is more useful than trying to make a final identification alone.

What should you do after a suspected sighting?

The French agriculture ministry recommends capturing the adult when this can be done easily, then contacting the DRAAF, the regional agriculture and plant-health authority. A report should include useful evidence: one or more photographs, the exact place, the date and the plant on which the insect was seen. Bourgogne-Franche-Comté also provides an online reporting form.

  1. Photograph the insect before and after capture, trying to show the white tufts.
  2. Record the context: town, exact location, date, host plant and number of insects seen.
  3. Keep the captured specimen in a closed container and do not transport it unnecessarily.
  4. Contact the regional DRAAF or plant-health service and follow its instructions.

Do not apply an insecticide “just in case”. A product used without a diagnosis may kill non-target insects, create unnecessary exposure and make the site harder to assess. The tools mentioned by authorities — surveillance, physical measures, biological control or authorised treatments — are combined according to the location and official pest status. That decision belongs to the competent services, not to a rushed response in one garden.

How does the beetle travel?

Popillia japonica is often described as a hitchhiker. An adult can travel on a car, train, lorry, luggage, equipment or plants. Several French captures occurred close to motorways or major transport corridors. Larvae may also be moved in soil around the roots of plants intended for replanting.

This movement explains why a detection far from a known outbreak does not immediately prove local establishment. It also calls for extra attention after a journey and when buying or exchanging potted plants. The French ministry explicitly asks people to inspect garden plants and remain vigilant when swapping plants.

Climate is not a sufficient explanation for each interception. Human transport provides the route of arrival; abundant host plants and suitable conditions may then help the beetle establish. Keeping those steps separate avoids turning a precise plant-health alert into a vague climate story.

What should you inspect in a garden or small orchard?

The most useful monitoring is regular and targeted. Look at upper, sunlit leaves on grapevines, roses, fruit trees and berry plants. Check flowers and ripening fruit too. Chewed leaves are not proof by themselves: caterpillars, slugs, vine weevils and other beetles also leave feeding marks. Search for the insect and its anatomical features rather than diagnosing from damage alone.

If several similar beetles are grouped on one plant, document the approximate number without scattering them. For a recently purchased potted plant, keep the label or proof of origin; that information may help officials trace a possible movement route. Do not send the plant, its soil or green waste to another region until the doubt has been resolved.

These precautions are proportionate. They require no expensive equipment or specialist knowledge, yet they turn an ordinary observation into information that a surveillance network can use.

Why local exchanges also require care

Local supply chains shorten the distance between producers, gardeners and residents, but “local” does not automatically mean “free from plant-health risk”. A pot, root ball or plant can carry an organism that was invisible when the exchange began. For live plants, know the origin, inspect leaves and visible roots, and respect any official rules that apply in a demarcated zone.

Harvested produce is different from a rooted plant with soil, but it is still sensible to inspect it before transport. If a suspect insect is found on a crate or vehicle, reporting it is the right response; releasing it somewhere else is not.

Neighbourhood tools can support that same culture of responsibility. Seeed enables individuals and producers to give, sell or swap harvests and local products with people around them. That connection never replaces official plant-health surveillance. It can, however, go with simple habits: describe where a batch came from, inspect what is being moved and pause a plant exchange when there is a credible concern.

Key points

The Japanese beetle was detected repeatedly in France in 2026, but the official status still refers to transient incursions under eradication. Its metallic colour is noticeable, while the white abdominal tufts are the more useful identifying feature. If you think you have found one, photograph it, record the place and host plant, capture it if that can be done simply, and contact the regional DRAAF. A precise alert is more valuable than a rushed treatment.

Sources

Image credit

Arthur E. Miller, USDA APHIS PPQ, Bugwood.org — Japanese beetles on raspberry plants, Wikimedia Commons — Creative Commons Attribution 3.0 United States (CC BY 3.0 US). The image can be cropped; no edit is embedded in the source file.