Explore Plants

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
    
 

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

Tuesday - November 03, 2009

From: Austin, TX
Region: Southwest
Topic: Trees
Title: Are the moths in my Austin, TX live oaks harmful?
Answered by: Joe Marcus

QUESTION:

It is November and my live oak trees are full of moths. What are they and are they harmful to my trees?

ANSWER:

The insects you're seeing is almost certainly not moths, but butterflies.  Texas is currently experiencing an explosion in the population of American Snout butterflies, Libytheana carinenta.  These population explosions regularly occur when certain climatic conditions are met.  During these times, billions of adult American Snout butterflies - which do resemble moths - may take to the air in Texas.  Other states may see similar flights of this species, but in much smaller numbers.

The good news is that American Snouts do not feed on Live Oak, only hackberry.  In fact, while the caterpillars of this species can, when the leaves are just emerging, feed on the foliage of any hackberry species, they actually feed almost exclusively on Celtis ehrenbergiana (spiny hackberry), listed as Celtis pallida by some sources.  For more on the interesting life history of this butterfly species, see this excellent article on American Snout "migrations."

The adult American Snouts visiting your live oaks are probably attracted to the nectar-like secretions of plant-sucking insects, like aphids, living on your oaks.  Though aphids and other insects like them do take some food and energy from Live Oak trees, they rarely cause enough damage to be of any real concern.  For more information on oak pests, please visit this webpage from the Forest Pests website.

 

More Trees Questions

Effect of pecan trees on pool deck from Clovis CA
February 14, 2013 - I have pecan trees next to our pool deck. Are pecan trees invasive, will they lift up our pool deck?
view the full question and answer

Season to plant Pacific Wax Myrtle from Fallbrook CA
July 25, 2013 - Would like to know which season would be the best to plant Pacific Wax Myrtle in Fallbrook, CA area? I presently have invading bamboo, which I want to get rid of. Thank you!
view the full question and answer

Looking for a plant to use as a windbreak for a small orchard in Pineville LA.
February 28, 2011 - We are looking for a good plant to use as a wind break for our small fruit orchard.
view the full question and answer

Foundation plants for Albuquerque.
July 01, 2012 - Hello, I live in Albuquerque. I am looking for some native/xeric low water usage plants for foundation plants for my home. They will be foundation plants for a two story home that has a large ponde...
view the full question and answer

Plants for area around pool in Plano, Texas
October 13, 2009 - I just built an in ground pool in Plano, Texas and now want to landscape around it on my own. I am curious what plants/shrubs you recommend. There will be plants/shrubs on three sides of the pool. ...
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.