Invasive SpeciesJapanese barberry

Berberis thunbergii
FOUND by kirstl17
ID Confirmed
Quality checked by Stlouis97
Peer reviewed by Stlouis97
Field Notes
We investigated an open field at the Biddeford High School. The sun was shining bright with no clouds in the sky. The air was dry and very cold with temperatures around 25 degrees Fahrenheit. Frost covered the grass and leaves of many plants. The plants we observed grew along a metal fence surrounding the track.
A sketch of our study site.
Supporting Evidence
Photo of my evidence.
The stem grows in a zig-zag formation. There is one thorn at each 'joint' and small cluster of leaves. We think this species is the Japanese barberry because it has only one thorn at each joint, unlike European and American barberry which have one to three thorns at each joint.
Photo of my evidence.
Bright red berries will start to appear on this plant after September. The appearance of these berries is part of the seasonal change of the Japanese barberry.
Photo of my evidence.
The leaves of this plant are originally green and oval-shaped with smooth edges. They appear to be about two to four centimeters in length, however, our group did not get a chance to get an exact measurement. Also after September, the leaves of the Japanese barberry will turn purplish-red. The smooth leaves of the Japanese barberry separate the plant from the European and American barberry as they have leaves with toothed edges.
Species Observation: Species Looked For
Did you find it?: 
I think I found it
Scientific name:
Berberis thunbergii
Common name:
Japanese barberry
Sampling method: 
Just looking around
Photo of our sampling method.
Place Studied
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Map this species
N 43.493748 °
W -70.472166 °
Observation Site Information
A photo of our study site.
Upland - Developed areas
Trip Information
Biddeford High School
Trip date: 
Tue, 2013-10-29 08:02
Town or city: 
Type of investigation: 
Species Survey


Wicked awesome sketch. I hope it gets on the Best VS Sketches page!

Great evidence. It's awesome that you're aware of the species that look similar to Japanese barberry.

Thanks for reporting it. There are tons of Japanese barberry observations streaming in from southern Maine this fall - go check out the map ( to see where it's been found nearby. Where do you think it might be found next?