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 - March 06, 2011

From: Washington, DC
Region: Mid-Atlantic
Topic: Trees
Title: Are baldcypress trees (Taxodium distichum) self-fertile
Answered by: Nan Hampton

QUESTION:

We are considering planting a bald cypress in a grassy children's play area that has fair amount of clay in the soil and receives a good amount of rain water from an adjacent slope. This seems a good choice for a shade tree since we would like to choose native plants that offer wildlife benefits, but we don't have room for TWO baldcypress trees. Does this monoecious plant produce more seed when cross pollinated with other baldcypress plants (like corn does) or are they self fertile?

ANSWER:

This Mr. Smart Plants did considerable database and Internet searching and consulted with several other Mr. Smarty Plants, but none of us has been able to find any specific information about whether Taxodium distichum (Bald cypress) is self-fertile or not.  Here is what I didn learn, however:

In angiosperms (flowering plants) there are several ways to insure that plants don't self-fertilize since self-fertilization decreases genetic diversity.  (You can read an outline of a lecture from Missouri State University about "Plant Sex" with information about angiosperm barriers to self-fertilization.)  For instance, the plants may be dioecious (male flowers occurring on a different plant from the female flowers).  This mechanism occurs in some gymnoperms [e.g., Juniperus ashei (Ashe juniper) and Juniperus virginiana (Eastern red cedar)].  Another way is that the male and female reproductive parts on the same plant may mature at different times.  I wasn't able to find any reference to this being the case in Taxodium sp. or any other gymnosperm.  The most common way that angiosperms avoid self-fertilization, however, is by being self-incompatible.   When a pollen grain from a plant lands on a stigma of the same plant, biochemical signals allow the plant to recognize the pollen as its own pollen and prevent it from fertilizing the ovule by inhibiting the growth of pollen tube.  This system, however, doesn't appear to function in gymnosperms.  A 1986 paper by Michael S. Zavada and Thomas N. Taylor ("The role of self-incompatibility and sexual selection in the Gymnosperm-Angiosperm Transition: a hypothesis."  THE AMERICAN NATURALIST, Vol. 128, no. 4, October 1986) states:  "The origin of intraspecific self-incompatibility (SI) is regarded as a significant event in the evolution of flowering plants. ... There are no documented cases of SI in gymnosperms."  

So, the upshot is that I don't see any reason why you can't plant just one baldcypress and still expect to get an optimal production of seeds for wildlife.  Gymnosperms are wind pollinated and this aids in self-fertilization as well as cross-fertilization.  If there are other Taxodium distichum trees in the general vicinity, your tree might even be pollinated by the pollen brought in by the wind from those.

 

More Trees Questions

Healthy black walnut trees from volunteer saplings
May 07, 2008 - We just purchased a piece of property in the Texas Hill Country. There is a stump of a large black walnut tree that has four healthy looking samplings shooting up. Each is about 10 feet high. The o...
view the full question and answer

Why doesn't my Possum Haw have berries this year?
May 20, 2010 - A possumhaw holly has no berries as of mid-May. I planted this possumhaw last summer - it had lots of berries. Why would it have no berries this year? This spring I have two yaupons with lots of b...
view the full question and answer

Non-native crape myrtle resistance to deer from Annapolis MD
April 06, 2013 - Is Crape Myrtle tree resistant to deers? Thank you.
view the full question and answer

Need advice for pruning a young Bur Oak tree in Austin, TX.
November 02, 2010 - I grew a beautiful bur oak from seed, and three years later it is now taller than I am. I hate to cut anything off this tree and hurt it, but there are two branches that are rubbing together and growi...
view the full question and answer

Cypress trees near pool in Winter Park FL
August 17, 2012 - I live in Winter Park (Orlando) Florida. I have been gifted two potted cypress trees that I need to get into the ground. The only place I can plant them is in my backyard in between a stand of non-inv...
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.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center