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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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Thursday - October 14, 2010

From: Nashville, TN
Region: Southeast
Topic: Plant Identification
Title: Identification of thorny tree with lemon-like fruit
Answered by: Nan Hampton


What would be a small lemon like fruit that grows on a bush with large thorns? The fruit is about the size of a golf ball, kind of fuzzy yellow skin like a lemon and smells like a cross between an orange and a lemon. The flesh is like that of a lemon.


This sounds like Poncirus trifoliata (hardy orange or trifoliate orange), an introduced species from China.  It is listed on the Center for Invasive Species and Ecosystem Health website and by  If this isn't the plant you have seen, please take photos and send them to us and we will do our best to identify it.  Visit Mr. Smarty Plants' Plant Identification page to read the instructions for submitting photos.


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