En EspaÑol

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?


Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
rate this answer
1 rating

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




More Invasive Plants Questions

Getting rid of Japanese bindweed in Massachusetts
February 04, 2009 - How do you get rid of Japanese Bindweed (mile-a-minute)?
view the full question and answer

Invasive iceplant in Hawaii
October 29, 2008 - Last time I checked Hawaii was in North America. Invasive or not, iceplant continues to be a much used ground cover etc for golf courses, sides of the freeway and many many City and County projects pr...
view the full question and answer

Problems with Habiturf in Austin
May 10, 2014 - I have been trying to establish a Habiturf lawn in my back yard. It is approximately a 1,000 square foot area and this last seeding was the third over about one and a half years. I just recently over ...
view the full question and answer

Eliminating kudzu from Richmond KY
March 26, 2014 - I live in Richmond KY, Kirksville area. I have noticed that Kudzu has started to grow in my patch of land next to the creek. How can I get rid of this before it becomes a big problem?
view the full question and answer

Removal of Ashe juniper trees
April 19, 2015 - I have 15 acres with scattered huge oak and elm trees with tens of thousands of Ashe Juniper (cedar) trees 2” to 10” in diameter growing within the drip zone of the hardwoods. How do I take out the c...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2015 Lady Bird Johnson Wildflower Center