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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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Sunday - April 26, 2009

From: Greenwell Springs, LA
Region: Southeast
Topic: Non-Natives
Title: Thorns on non-native orange trees in Greenwell Springs, LA
Answered by: Barbara Medford


Navel orange tree has thorns, why is this?


The orange (Citrus sinensis) is a hybrid, possibly of pomelo (Citrus maximus) and tangerine (Citrus reticulata); it originated in Southeast Asia. As such, it is out of our area of expertise at the Lady Bird Johnson Wildflower Center, where we concentrate solely on plants native not only to North America but to the area in which they are being grown. This Floridata website, Citrus Sinensis, has more information, and specifically says, "The twigs on many orange cultivars are thorny."

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