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Q. Who is Mr. Smarty Plants?

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Sunday - March 20, 2016

From: Pearl, MS
Region: Southeast
Topic: Problem Plants, Herbs/Forbs
Title: Identity of stinging weed in Pearl, Mississippi
Answered by: Nan Hampton


I live in Pearl, MS. Yesterday I pulled a weed that right away started stinging my hand and in a few hours turned into stinging numbness. The weed has dark green heart shaped leaves with purple veins the largest about the size of a quarter. I can see these little hair like things on the stem. Thank you so much.


There are several possibilities for stinging plants in Mississippi, but from your description it sounds as if the plant you encountered was Urtica chamaedryoides (Heartleaf nettle).  The USDA Plants Database distribution map shows it occurring in Mississippi.  Here is more information about Urtica chamaedryoides from University of Florida IFAS Extension and here are photos from the University of Texas School of Biological Sciences.

Other possibilities for stinging plants that occur in Mississippi are:

Urtica dioica (Stinging nettle)

Another possibility is Tragia cordata (Heartleaf noseburn)  Here are more photos from Discover Life

There are other species of Tragia that are found in Mississippi, but they don't generally fit your description:

Tragia smallii (Small's noseburn)  Here is a herbarium specimen from Calhoun County, Florida.

Tragia urens (wavyleaf noseburn)  Here is a photo from Discover Life.

Tragia urticifolia (Nettleleaf noseburn )  Here are photos and more information from Carolina Nature.


From the Image Gallery

Heart-leaf stinging nettle
Urtica chamaedryoides

Heart-leaf stinging nettle
Urtica chamaedryoides

Heart-leaf stinging nettle
Urtica chamaedryoides

Stinging nettle
Urtica dioica

Stinging nettle
Urtica dioica

Heartleaf noseburn
Tragia cordata

Heartleaf noseburn
Tragia cordata

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