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Tuesday - August 18, 2009

From: Aurora, MN
Region: Midwest
Topic: Poisonous Plants
Title: Toxic effect of mulberry fruits and sap
Answered by: Nan Hampton


What would be the toxic effect of the unripe fruit of the mulberry tree or the white sap?


The Poisonous Plants of North Carolina database lists both the North American native Morus rubra (red mulberry) and the introduced Morus alba (white mulberry) as mildly toxic.  The toxic parts are the unripe berries and the white sap from any part.  The symptoms are hallucinations and stomach upset.  This database says that it "causes only low toxicity if eaten". This is the only toxic plant database I could find, however, that listed it. 

Delena Tull in Edible and Useful Plants of Texas and the Southwest says that the pollen of these two trees causes hay fever.  She also says: 

"Unripe fruit and milky sap can cause gastrointestinal distress and some toxicity...The sap can cause a skin rash."

L. A. Peterson in A Field Guide to Edible Wild Plants of Eastern and Central North America says about both species:

"Unripe fruit and raw shoots contain hallucinogens."

Morus rubra

Morus rubra



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