|I have a project in Connecticut, and like many states they consider Jap. Barberry an invasive, unnacceptable species. Do you have any information or can offer an opinion on 'Helmond Pillar' as a potential invasive? The proposed use of the plant is for a foundation planting on a manicured lawn, Corporate campus.
|The listing for Berberis thunbergii at the University of CT Plant Database does include the designation of Demonstrated Invasive Tendency -- "This species has demonstrated an invasive tendency in Connecticut, meaning it may escape from cultivation and naturalize in minimally managed areas." Whether you would consider a manicured corporate campus a minimally managed area is up to you, but you could certainly consult with the local county extension for the area where the county is located and see if it is of special concern there.
You might want to take a look at what they say about for yourself. Here is the listing for this plant. (You may need to cut and paste the entire complete url into your browser ot make it work correctly.)
I would also strongly suggest you read the explanation about the advisory which may help you understand its intent better.
I hope this helps you in your research.