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Thursday - August 23, 2007

From: Riverhead, NY
Region: Northeast
Topic: Non-Natives
Title: Distribution of Non-Native Royal Empress Tree
Answered by: Jimmy Mills


I was wondering if you could give me the statistics for the Royal Empress Tree in the Long Island area. I have two and have read numerous articles online regarding them being invasive through the root system and seed pods that will sprout after the purple/blue flowers in the spring. The trees I have are approx 2 years old. What is the reproduction rate (invasiveness) on Long Island for this kind of tree? Any information you could give me regarding care, maintance, and removal would be greatly appreciated.


Empress Tree (Paulownia tormentosa), aka Princess Tree, is native to China, and is distributed in 25 states in the US from Massachusetts to Florida and west to Texas. In most of its range, it is considered an invasive plant. However, the Invasive Plant Council of New York State does not list it as such, but the Invasive Plant Atlas of New England does.

As you have probably noticed from your two plants, growth is very rapid. Your plants could become reproductive in six to eight years, and at that time, each could potentially produce 20 million seeds a year. That could result in a lot of seedlings.

An article from the Plant Conservation Alliance describes the biology of the plant along with measures to control its growth. More detailed information about care of Paulownia is available at this website.

If you plan to remove your princess trees, you might consider these native alternatives:

Ilex opaca (American holly)

Cercis canadensis (eastern redbud)

Amelanchier canadensis (Canadian serviceberry)


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