That's Invasive? Japanese Barberry ~ Berberis thunbergii

Photo Credit: John Ruter, University of Georgia
Native to: Eurasia

Best Method of Removal: Cut and treat woody stems with glyphosate (early spring is a good time). Beware of sharp thorns!

Interim Measures: Cut back after flowering to prevent seed formation

Native Alternatives: Bush Honeysuckle (Diervilla lonicera), Serviceberries (Amelanchier species), Black Chokeberry, Snowberry, Downy Arrowwood Viburnum

Cultivars Sold in the Nursery Trade: Bagatelle, Burgundy Carousel, Concorde, Crimson Pygmy, Emerald Carousel, Golden, Golden Carousel, Golden Nugget, Helmond Pillar, Kobold, Lime Glow, Rose Glow, Royal Burgundy and more!
I found this Japanese Barberry plant growing at a Carver County park last spring, and just this week found it growing at an Eden Prairie park in Hennepin County. Both were found in fairly dense shade in woodlands.

I knew that the Wisconsin DNR had this horticultural ornamental listed as invasive but this was the first time I had seen an escapee in Minnesota. In fact, "Japanese barberry has been reported to be invasive in twenty states and the District of Columbia. Due to its ornamental interest, barberry is still widely propagated and sold by nurseries for landscaping purposes in many parts of the U.S." (State of Pennsylvania Fact Sheet)

Photo credit: Leslie J. Merhoff, University of Conneticut
Japanese Barberry flowers in late May to early June in Minnesota producing creamy yellow-white flowers that dangle below the thorny branch. These flowers produce red berries in late summer to early fall in Minnesota.

Photo credit: Barry Rice,
"Barberry produces large numbers of seeds which have a high germination rate,  estimated as high as 90%." (State of Pennsylvania Fact Sheet)

The Barberry berries are eaten by birds and thus distributed to new places to germinate.

If you have Japanese Barberry in your landscape, do your part by replacing it with a native shrub or non-invasive exotic ornamental.

You can help stop the sale of Japanese and European Barberry in nurseries. Do not buy this shrub and tell your local nursery that this plant is invasive!

Map of Japanese Barberry Reported Sightings