En Español

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

Thursday - September 01, 2011

From: Fresno, CA
Region: California
Topic: Plant Identification
Title: Origin of thorned plant-like object falling from the sky
Answered by: Nan Hampton

QUESTION:

This morning while walking I felt a prick on my arm, like something had bitten me. I looked and saw what appeared to be a very tiny little plant with a thorn on it sticking out of my arm. I pulled it out and in a few moments felt another one. Now it is evening and the site still itches. Any idea what it might have been? I was not in any heavy brush but there were some tall trees overhead.

ANSWER:

The most likely possibility I can think of is that you were struck by small leaflets with spiny stipules. Stipules are the small paired appendages at the base of the petiole (stem) of a leaf.  Several species of Central American acacias have impressively large spiny stipules.  Robinia pseudoacacia (Black locust) is a species native to North America with a bit more modest stipular spines.  It has been reported in California in counties adjacent to Fresno County.  Click "California" on the USDA Plants Database distribution map to see counties where it has been reported in California.  You can also see the spiny stipule on the photograph on that page.  Here is a drawing showing the leaves and the spines and here is a photo.  The tree can grow from 40 to 100 feet tall and is considered invasive in many areas, including California.  One acacia relative, Prosopis pubescens (Screwbean mesquite), with spiny stipules grows in Fresno County and can reach a maximum of about 30 feet.  Here are photos showing the spines.  An insect or small mammal feeding on the tree, could possibly chew on the newly formed leaflets at their base and cause them to fall from the tree with the stipular spines attached.  One species of ant in Africa prunes new leaf shoots (presumably along with the spiny stipules) from acacia trees there.  (Young, T. P., M. L. Stanton & C. E. Christian.  2003.  Effects of Natural and Simulated Herbivory on Spine Lengths of Acacia drepanolobium in Kenya.  Oikos Vol. 101, no. 1: 171-179). 

Whatever the prickly plant-like objects are, it seems likely they fell from the tall trees you said you were walking under.  Your best bet, then, is to go back and try to determine what the trees are.  If you have photos of the trees and/or the prickly object, you should visit our Plant Identification page to find links to plant identification forums that accept photos for identification.

 

More Plant Identification Questions

Plant identification
July 10, 2014 - I am trying to identify a wildflower that has popped up after a big rain. It is under a foot tall---blooms a yellow bloom in the evenings. It has long narrow leaves sort of like a rosemary. It grows f...
view the full question and answer

Plant identification
June 01, 2010 - I have a grandchild that said the seed pod on a plant that looks like a clover is edible. It has clover like leaves and a little yellow flower. I did taste it and it kind of taste like a pickle. Th...
view the full question and answer

Identity of fleshy three-leaved vine in Central Texas
June 20, 2015 - I have a 3 leaved evergreen vine, that I assume is a central Texas native, growing in my yard in a non irrigated mostly shady spot. It has a strong odor when touched and looks and feels like a succule...
view the full question and answer

Identifying
September 01, 2007 - i have a tree that i cannot identify. the leaf looks like a "pot plant"(yes, cannabis!!), but the leaf does not have serrated edges. it has a long bloom of numerous small white flowers that form a s...
view the full question and answer

Identity of cinnamon-scented bush from Pennsylvania
May 23, 2015 - I had a "bush" in PA that the woman who sold it to me called a cinnamon bush. It had long branches with large (approx 5" long and 3" wide) dark green leaves attached evenly along each side of the...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | JOBS | SITEMAP | STAFF INTRANET
© 2016 Lady Bird Johnson Wildflower Center