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Monday - September 22, 2008

From: Paw Paw, IL
Region: Midwest
Topic: Invasive Plants
Title: Information about invasive Paulownia tree
Answered by: Nan Hampton


What genus and species and family is this Royal Paulownia tree I hear about? Is it Elm? Linden? Dogwood? Is it a weed? thank you


Paulownia tomentosa (royal princess tree), a native of China, is a member of the Family Scrophulariaceae (Figwort Family).  There are no trees native to North America that are in this family—elm is in the Family Ulmaceae, linden is in the Family Tiliaceae, and dogwood is in the Family Cornaceae.  A few familiar North American plants in the Family Scrophulariaceae are:  the paintbrushes (Genus Castilleja), the monkey-flowers (Genus Mimulus) and the louseworts (Genus Pedicularis).

Mr. Smarty Plants certainly considers it a weed!  Please note what Texas Invasives says about it: 

"Princess tree is an agressive ornamental tree that grows rapidly in disturbed natural areas including forests, streambanks, and steep rocky slopes."  

It is also is listed in the Invasive Plant Atlas of New England, in the Plant Conservation Alliance's Alien Working Group Least Wanted list and the Federal and State Noxious Weeds list.

If you are considering planting a royal paulownia tree, we urge you to consider these native alternatives:

Amelanchier arborea (common serviceberry)

Cercis canadensis (eastern redbud)

Cornus florida (flowering dogwood)

Ilex opaca (American holly)

Morus rubra (red mulberry)

Lindera benzoin (northern spicebush)

Sassafras albidum (sassafras)

Amelanchier arborea

Cercis canadensis

Cornus florida

Ilex opaca

Morus rubra

Lindera benzoin

Sassafras albidum




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