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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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Wednesday - March 21, 2012

From: Conroe, TX
Region: Southwest
Topic: Invasive Plants, Non-Natives, Plant Identification
Title: Identity of rubbery-looking tree with long green thorns
Answered by: Nan Hampton

QUESTION:

I am trying to identify a tree that has a green rubbery look with long, sharp, green thorns. This tree is on my property in Conroe, TX and the soil type is Gladwater clay frequently flooded.

ANSWER:

This sound like Poncirus trifoliata [syn. Citrus trifoliata] (trifoliate orange).  It is native to China and Korea and is considered invasive in North America.  Here are more photos and information.
 

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