Invasive SpeciesJapanese knotweed

Fallopia japonica
FOUND by littleriver15
ID Confirmed
Quality checked by Lillian
Peer reviewed by Lilian
Field Notes
Clear of debris and without many stems, it was quite easy to see the brown leaf-covered dirt around. Lots of dead stems, small weeds, and dead leaves from the trees above make it difficult to see the smaller stems of Japanese Knotweed on the ground. The heart-shaped leaves are multicolored green and yellow. Birds chirp and my classmates search their own quad-rats for the invasive plant. It was quite surprising that there was not a lot of Japanese Knotweed in the quad-rat, and some even dead.
A sketch of our study site.
Supporting Evidence
Photo of my evidence.
As you can see in the picture, the Japanese Knotweed leaves are in the shape of hearts. There was an average length of about 7 inches, as well as an average width of about 6 inches. A thick, pale green line runs down the middle and many smaller veins branch off from it. This is identical to the pictures on the Vital Signs species card for Japanese Knotweed.
Photo of my evidence.
As you can see in the picture, the plant held the leaves in an alternating zig-zag pattern such as; left, right, left, right or vice versa depending on the plant. Which, according to Vital Signs species card, is what Japanese Knotweed looks like.
Photo of my evidence.
What I saw, also what is shown in the picture, is a green, bamboo like, hollow stem. I know from Vital Signs species cards that Japanese Knotweed's signature bamboo like stem can be different shades of green. Those are all colors of the hollow stems which sprout from the dirt covered ground.
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: 
Less than 1/4 covered
Flower (plants)
Vegetative structures (plants)
Sampling method: 
Quadrat (randomized- placement)
Photo of our sampling method.
Place Studied
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Map this species
N 43.664010 °
W -70.446185 °
Observation Site Information
A photo of our study site.
Upland - Forest
Trip Information
Weeks Road Trail System
Trip date: 
Fri, 2018-10-12 08:00
Town or city: 
Type of investigation: 
Species and Habitat Survey
Habitat Observations
Species diversity: 
2 different species
Evidence of vectors: 
Walking trail
Recent disturbance
Tree canopy cover: 
Between 1/4 and 1/2
Soil moisture: 
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