Rent Shop Volunteer Join

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.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Share

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
Not Yet Rated

Wednesday - June 13, 2012

From: Devon, PA
Region: Mid-Atlantic
Topic: Poisonous Plants
Title: Is Asclepias incarnata poisonous to dogs?
Answered by: Anne Ruggles

QUESTION:

Is Asclepias incarnata safe in a farm/yard with plenty of dogs running around? What happens if a dog eats the leaves or seeds or pods? Is eating any of these fatal to dogs?

ANSWER:

Butterfly weed, milkweed, chigger-plant these are all common names for the plants of the genus Aesclepias which includes A. incarnata  which you ask about. In short, yes, the genus is poisonous. All parts of the plant are poisonous.

According to many sources including North Carolina State University, the University of Pennsylvania School of Veterinary Medicine, the ASPCA, and the Wildflower Center, all parts of the plant are poisonous in “large quantities.” It appears that livestock are most likely to ingest the plant.

Clinical signs of poisoning include profuse salivation, incoordination, and violent seizures. Early signs of poisoning are followed by bradycardia or tachycardia, arrhythmias, hypotension and hypothermia.  Death may occur from 1-3 days after ingestion.

However, the plants are premier food sources for butterflies, especially for Monarch butterflies. In the mid 1800s, naturalists observed that birds avoided eating butterflies whose larvae fed primarily on milkweed. It was later shown that the feeding larvae accumulated emetic cardiac glycosides that were retained and even concentrated in adult butterflies. Birds that ate the butterflies containing these glycosides vomited shortly after feeding and learned to avoid butterflies having the pattern typical of Monarch butterflies. Viceroy butterflies have evolved the ability to mimic the monarch’s appearance thus avoiding predation by birds who mistake the mimic for the distasteful monarch. 

 

From the Image Gallery


Swamp milkweed
Asclepias incarnata

More Poisonous Plants Questions

Non-toxic Groundcover for North-Central Texas
April 07, 2011 - I need a creeping ground cover for shade that is non-toxic to dogs. I had planned on Swedish ivy until I read it was toxic. Is Asian jasmine toxic? Or, do you have any suggestions?
view the full question and answer

Identification of plant with orange sap that glows at night
June 06, 2012 - I was just pulling up a plant and noticed that its sap was a kind of orange then I noticed it glowing orange at night. What kind of plant is this and is it dangerous?
view the full question and answer

Poisonous plant in Ohio with hydrangea-like flower
June 09, 2008 - Dear Mr. Smarty Plants, I was sure that I had read that there is a poisonous bush that is native to Ohio that has flowers something like a white hydrangea..or was it queen ann's lace? I believe the ...
view the full question and answer

Wintering over an Angel Trumpet in Kentucky
September 20, 2008 - I have an Angel Trumpet on my deck in LaGrange,Ky -Can I plant it out in the yard now or do I have to take it in the house for the winter- It is 5 feet tall and I have no room in the house! Help!-Than...
view the full question and answer

Is Phyla lanceolata (frogfruit) poisonous to dogs fromTitusville FL?
June 01, 2014 - Is Phyla lanceolata, also called Fogfruit, Lanceleaf Fogfruit, or Northern Fogfruit, toxic to dogs? We have it growing amongst our grass. I can't find it on any toxic plant list.
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.