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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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Sunday - July 27, 2008

From: Lake Francis, MB
Region: Canada
Topic: Poisonous Plants
Title: Plant with poisonous thorns
Answered by: Nan Hampton

QUESTION:

Is there a bush or tree out there that has thorns on it that can make you swell and cause you to feel like you can hardly move you're whole hand.

ANSWER:

I searched the Canadian Poisonous Plants Information System for such a plant in Manitoba. I found the following two plants with stinging hairs which might be considered very small thorns, but I could find nothing with large thorns that has the effect that you mention.

Laportea canadensis (Canada nettle) has stinging hairs that can cause pain and discomfort. Here are photos and more information.

Urtica dioica (stinging nettle) also has stinging hairs that give a painful sting, swelling, itching and numbness. More information and photos.

If you didn't actually see the thorn or thorns that caused this, you might consider that you were bitten by a spider or stung by some insect.


Urtica dioica

 

 

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