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

Monday - June 09, 2008

From: Hudson, OH
Region: Midwest
Topic: Poisonous Plants
Title: Poisonous plant in Ohio with hydrangea-like flower
Answered by: Nan Hampton

QUESTION:

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 flowers could cause severe respiratory distress. Any ideas of what this shrub could be?

ANSWER:

Hydrangea spp. can be toxic (nausea, stomach pain, vomiting, sweating) but only if eaten in large quantities. Queen Anne's lace (Daucus carota) leaves cause skin irritation, but are edible if cooked properly. I think it is more likely that you read about one of the "hemlocks".

Poison hemlock (Conium maculatum) is highly toxic with a large variety of symptoms. This is an introduced species from Europe and is, supposedly, what Socrates drank when sentenced to death for "refusing to recognize the gods recognized by the state" and "of corrupting the youth". Even though it is introduced it has spread over almost all of North America, including most of Canada.

Water hemlock (Cicuta maculata), a native plant of the same family (Family Apiaceae, Carrot Family), is equally as toxic with similar symptoms. This native species has a similar distribution.

You can find more information about these two from the Canadian Poisonous Plants Information System by searching on their botanical names. For Conium maculatum one of the "General symptoms of poisoning" under "Humans" is "death by asphyxiation". For Cicuta maculata, under "General poisoning notes", death is listed as "from asphyxiation".  The Indiana Plants Poisonous to Livestock and Pets data base lists these two in their "Extremely  Toxic" list.  These are definitely two plants to be avoided!


Hydrangea arborescens

Cicuta maculata

 

 

 

 

More Poisonous Plants Questions

Will Calycanthus floridus (Eastern sweetshrub) grow near black walnut trees?
April 01, 2012 - Will Calycanthus floridus survive if planted near Black Walnut trees? If not, can you recommend a similar bush that will?
view the full question and answer

Can a dog die from eating a holly bush?
January 12, 2016 - Can a dog die from eating a holly bush?
view the full question and answer

Is Thalia dealbata toxic to dogs?
May 16, 2011 - A pond in a park frequented by dogs contains Thalia dealbata and I have seen numerous dogs eating the roots with relish, which we discourage, of course. They seem to really enjoy it though. Aft...
view the full question and answer

Is Penstemon Poisonous to Dogs?
February 21, 2016 - Is Penstemon palmeri poisonous to dogs? I couldn't find in ASPA guide.
view the full question and answer

Is Bignonia capreolata (Crossvine) known to cause skin irritation
July 23, 2013 - Is Crossvine (Bignonia capreolata L.) known to cause a rash? We are trying to identify the source of a rash-after-gardening, and have not seen any of the big three (poison ivy, poison oak, poison suma...
view the full question and answer

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