Invasive SpeciesJapanese knotweed

Fallopia japonica
FOUND by Penguin
ID Confirmed
Quality checked by barnacle
Peer reviewed by blobfishy
Field Notes
I'm happy because it's nice outside, and we get to learn about the environment. I can see the flowers that are on the plant, hear the bees and animals around the plant, and I can smell the flowers. I was surprised by how much knotweed there was. It was everywhere. My partner and I found that after some investigation we were able to identify that the plant was Japenese Knotweed and not Giant Knotweed.
A sketch of our study site.
Supporting Evidence
Photo of my evidence.
It was easy to identify if our plant that we were investigating was Japanese Knotweed. The leaves were a major factor to help identify of the plant was in fact Japanese Knotweed. The leaves of the Japanese Knotweed are very specific. They are a large spade-like shape, with a pointed top and smooth edges. The leaves were about the size of a small hand. Several are on one stem, and the flowers dangle below them or rest of the top of the leaves.
Photo of my evidence.
Another thing that helped us identify that the plant was Japanese Knotweed was the stem of the plant. The stem was hollow, and looked like bamboo. It had swollen joints that were solid on the inside to keep the stem from collapsing. We found pieces of the branches on the ground and looked inside of them, they were hollow, except for the joints. We also found a kind of nest inside one of the sticks. It looked like there was pieces of dried grass in it that a bug might of built.
Photo of my evidence.
The flowers on the plant were also helpful to our investigation. The were small, almost too tiny to see the details. They are white with small petals and are scattered all around the branches and leaves. They either droop down or lay across the stem of the knotweed or lay on the leaves. The flowers were just as useful as the leaves and the stem. The giant knotweed and Japanese knotweed are difficult to tell apart, so we used the flowers as guides. The giant knotweed flowers are all drooping down, and the length of the stem is longer, but on Japanese knotweed, some flowers stick up and aren’t as long.
Species Observation: Species Looked For
Did you find it?: 
I think I found it
Scientific name:
Fallopia japonica
Common name:
Japanese knotweed
Count of individuals: 
Flower (plants)
Pollinators (plants)
Eggs (animals)
Sampling method: 
Quadrat (user-placement)
Photo of our sampling method.
Place Studied
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Map this species
N 44.811221 °
W -68.755755 °
Observation Site Information
A photo of our study site.
Upland - Developed areas
Trip Information
Cohen School grounds
Trip date: 
Wed, 2018-09-12 09:48
Town or city: 
Type of investigation: 
Species and Habitat Survey
Habitat Observations
Species diversity: 
2 different species
Evidence of vectors: 
Paved road
Recent disturbance
Tree canopy cover: 
Between 1/4 and 1/2
Soil moisture: 


Great work getting the picture of the hollow stem.