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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.

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

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Friday - March 07, 2008

From: Waterford, CA
Region: California
Topic: Invasive Plants
Title: Information about empress tree (Paulownia tomentosa)
Answered by: Nan Hampton

QUESTION:

I have an Empress Tree, 3 yrs old, and the limbs grow straight out from the trunk about 2-3ft and then grow straight upward. When do they start to grow outward for a canopy??

ANSWER:

The focus and expertise of the Lady Bird Johnson Wildflower Center are with plants native to North America. Our mission statement reads:

"The mission of the Lady Bird Johnson Wildflower Center is to increase the sustainable use and conservation of native wildflowers, plants and landscapes."

Since the empress tree (or princess tree) Paulownia tomentosa is a native of China, having been introduced to North America in the 1800s, we are not the ones to be asking about its care. In fact, we would urge to replace it with a native, since this tree appears on many "invasive species" lists:

Invasive Exotic Pest Plants in Tennessee,

Connecticut State-listed Noxious Weeds,

Plant Conservation Alliance's Alien Plant Working Group 'Least Wanted' List,

Southeast Exotic Pest Plant Council Invasive Plant Manual,

Global Invasive Species Database,

TexasInvasives.org

Quoting from the Texas Invasives database:

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

I'm not sure what features of the empress tree attracted you (shade, blossoms, fast growth, canopy) but here are some native alternatives with attractive features:

Acer negundo (boxelder)

Fraxinus dipetala (California ash)

Fraxinus latifolia (Oregon ash)

Umbellularia californica (California laurel)

If you are looking for canopy, you can't go wrong with Quercus agrifolia (California live oak). For a thorough discussion of California oaks, visit Las Pilitas.com.

 


Acer negundo

Umbellularia californica

 

 

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