En EspaŅol

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
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
 
rate this answer
Not Yet Rated

Sunday - September 12, 2010

From: Jarrell, TX
Region: Southwest
Topic: Cacti and Succulents
Title: Prickly cactus in Williamson County, Texas
Answered by: Nan Hampton

QUESTION:

Dear Mr. Smarty Plants, Can you tell me what species of prickly pear cactus we have here in Williamson County? I see two listed as being here in Texas. One is the Plains variety and the other is a Lindheimer. Are either of these our central Texas native prickly pear?

ANSWER:

We are certain that Opuntia engelmannii var. lindheimeri (Texas pricklypear) occurs in Williamson County and pretty certain that  Opuntia macrorhiza (plains prickly-pear) also occurs there.  Opuntia phaeacantha (brownspine prickly pear) and Opuntia humifusa (low prickly pear) have also been reported in Williamson County.

So, why aren't we absolutely sure what's in Williamson County?  Because not all Texas counties have been completely surveyed, reported and verified by a botanical authority.  When we are asked which species occurs in a particular location, we have several sources we can check for species in Texas counties:  the USDA Plants Database, the University of Texas Plant Resources Center's Flora of Texas Database, and the Atlas of the Plants of Texas by B. L. Turner, H. Nichols, G. Denny and O. Doron.  

Generally, the first one we check is the USDA Plants Database. By selecting to do an Advanced Search in the Search column, we can choose 'Texas: Williamson' under "County Distribution" in the first section of choices and then scroll down to section 2 (Taxonomy) and type in 'Opuntia' in the "Genus" slot. Next we scroll to the bottom of the page and click on "Display Results" to learn that Opuntia engelmanii is the only species of Opuntia recorded in the USDA Plants Database in Williamson County, Texas.  If you click on Texas on the distribution map, you will see that Williamson is one of the counties highlighted.  You will also see that there are 4 different varieties shown for Texas. If you click on each of the distribution maps for those 4 varieties, you won't find Williamson County highlighted; but you will find that the distribution of  Opuntia engelmannii var. lindheimeri (Texas pricklypear) comes closest to Williamson County.  You can also see a statement underneath the USDA Plants Database that says "Our county data are based primarily on the literature, herbarium specimens, and confirmed observations. However, not all populations have been documented, so some gaps in the distribution shown above may not be real."

When we check Opuntia macrorhiza (plains prickly-pear) on the USDA Plants Database, we see that the distribution map shows it occurring in Travis and Burnet counties, but not in Williamson.

When we look at our other two sources, we find that no Opuntia species are reported in the "Flora of Texas Database" for Williamson County.  In the "Atlas of the Plants of Texas" vol. 1, pp. 218-219, both O. phaeacantha and O. humifusa are shown to occur in Williamson County; however, neither O. engelmanii nor O. macrorhiza are shown in Williamson County, but both are shown in Travis County and other counties adjacent to Williamson.

So, this is a very long answer to your question, but an explanation for why we aren't absolutely certain about the prickly pear species found in Williamson County.  Hopefully, someone is doing a botanical survey of the area and will report their findings.

 

From the Image Gallery


Texas pricklypear
Opuntia engelmannii var. lindheimeri

Common prickly-pear
Opuntia macrorhiza

Tulip prickly pear
Opuntia phaeacantha

Devil's-tongue
Opuntia humifusa

More Cacti and Succulents Questions

How to Control White Fungus on Prickly Pear Cactus?
July 04, 2013 - Is there any kind of spray for our prickly pear that will help with the white fungus that has appeared on it?
view the full question and answer

Possibly non-native succulent identification
March 27, 2008 - My mother has a plant that grows on a stalk, 2.5' tall, leaves are about 4-5" on the mature plant. The leaves are scalloped on the edges and seeds grown in the scallops & fall off and make new plan...
view the full question and answer

Is a yucca going to have a stalk from Sylvania OH
March 15, 2012 - Hi, I was wondering if the stalk on a yucca plant grows back every year after it is cut off? How to tell if it is going to have a stalk because some of my yucca's do not have one? Thank you for your ...
view the full question and answer

Killing a century plant from Burton TX
August 08, 2013 - How do you kill the century plant, they are taking over?
view the full question and answer

Nightflowering plants native to Northern Illinois
October 12, 2010 - Looking for any/all info on night flowering plants that are native to Northern Illinois.
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.

Bibliography

Atlas of the Vascular Plants of Texas (2003) Turner, B. L.; H. Nichols; G. Denny; O. Doron

Search More Titles in Bibliography

E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center