Invasive SpeciesJapanese beetle

Popillia japonica
FOUND by resorcinol
ID Confirmed
Quality checked by paraxanthine
Peer reviewed by sodium sulfate
Field Notes
We were happy because we found the beetle that we were looking for. It was a very nice day, and the temperature was perfect. It also smelled like autumn leaves. We saw leaves, people, plants, and beetles. We heard beetles, people talking, and cars. We smelled wet leaves and grass. We were surprised by what we found because we thought we would not find it because there were lots of leaves, it was cold out, and it was close to the end of beetle season. A few questions and problems we ran into were: Why did we not find any beetles the second day, but we found a lot the first day? Is it because it was warmer the first day? Maybe it was because the beetles prefer warmer weather.
A sketch of our study site.
Supporting Evidence
Photo of my evidence.
The species that we were looking for was the Japanese beetle, also known as the Popillia japonica. We think that we have found it because it matches the identification card in many different ways. This card stated that the Japanese Beetle length usually ranges from 14-15 millimeters long. When we measured, the beetle was nearly identical to that length: 15 millimeters. This helps distinguish that this could be the species that we were looking for, but we were not positive, because we had not collected enough evidence.
Photo of my evidence.
Different beetles come in many shapes, sizes, and colors. The Japanese beetle, according to the identification card, had a metallic jade thorax, a light brown wing case, and a black abdomen. This helped us distinguish the difference between the Japanese beetle and any other beetle. The beetle that we found fit these standards perfectly. It did have a metallic jade thorax and a light brown wing case. If you zoom into the picture, you can see two white stripes peeking out from under the beetle's abdomen.
Photo of my evidence.
Lastly, we found that the identification card stated that the beetle usually habituated in plants because their diet consists of leaves. We found this Japanese beetle on a Japanese Knotweed, which is one of their main habitats. We knew it was on the Japanese Knotweed because it was described on the identification sheet that it grew in small white flowers in finger-like bunches, and leaves that go up to 18 centimeters long. Using all of this evidence, we are fairly sure that we have successfully found the Japanese beetle.
Species Observation: Species Looked For
Did you find it?: 
I think I found it
Scientific name:
Popillia japonica
Common name:
Japanese beetle
Count of individuals: 
Less than 1/4 covered
Eggs (animals)
Sampling method: 
Just looking around
Photo of our sampling method.
Place Studied
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Map this species
N 44.811272 °
W -68.755723 °
Observation Site Information
A photo of our study site.
Upland - Developed areas
Trip Information
William S. Cohen Middle School
Trip date: 
Thu, 2015-09-24 10:38
Town or city: 
Type of investigation: 
Species and Habitat Survey
Habitat Observations
Species diversity: 
7 different species
Evidence of vectors: 
flys and crawls
Tree canopy cover: 
Open to 1/4 covered
Soil moisture: 


Picture of beetle next to ruler showed different measurement then stated in evidence. Could use a little more detail

Your question about the abundance of the beetle and the temperature is interesting. Have you thought about designing an investigation to help you test that? It would be neat to find out more.

Keep me posted.


We have not thought about doing an investigation, but it sounds like a really interesting idea and we will take you up on that. We will keep you posted if we have time to carry out the investigation. Thank you for taking the time to check out our investigation, and we are really curious about your idea of doing another investigation. Thank you very much.

-Hannah, Sophie, and Wells