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?


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

Thursday - April 14, 2011

From: Austin, TX
Region: Southwest
Topic: Trees
Title: Insects along branches of cedar elm
Answered by: Nan Hampton and Eric Beckers


I have a 10 foot Cedar Elm planted three years ago. The smaller branches have what looks like incubating red pellet-like insects in a soft, putty colored glob--one insect per glob. They are all along the branches. It looks as if those branches will not leaf out although uninfested ones are doing so. Are these insects causing permanent damage and can/should I do anything to get rid of them? Thank you.


I contacted Eric Beckers with the Texas Forest Service who agrees that your description sounds like lecanium scale insects.  University of California Integrated Pest Management (IPM) has a list of many scale insects (with links to photos of most) and their hosts.  Horticultural oil is a good treatment but it should have been applied in their overwintering stage to be most effective.   You can still do a summer weight oil application but you need to be very careful to avoid the new foliage when applying it.  Other possibilities for treatment are listed in the two links (above) about scales.  Eric reminds you that it is very important to maintain adequate moisture on those easily stressed new trees. 


More Trees Questions

Tree that looks like cedar elm but with smooth bark
August 09, 2014 - What tree looks like a cedar elm, but has smooth bark?
view the full question and answer

Madrone too close to house in Oregon
February 02, 2009 - I have a small Madrone tree (8ft tall) located approximatly 15 feet from my house, with a basement. Should I remove it? ie will it damage the foundation and is the tree strong enough that it will no...
view the full question and answer

Brown spots on native oak trees
June 16, 2015 - Hi, My native live oak trees are declining. The leaves have small brown spots that increase in size until the leaf dies and falls off, then the branch and then the entire limb. I have not watered the...
view the full question and answer

Propagation of maple tree in Canada
July 08, 2008 - I have a gorgeous maple tree in my front lawn and I want to plant more like it. The tree gives off very few keys a year so I want to make sure this works. How do I go about planting a maple key?
view the full question and answer

Retention of essential oils by Ashe Juniper wood from Austin
May 03, 2014 - I am looking for information on why local Austin Juniper/Cedar trees are so great at retaining essential oils for aromatherapy. I make pendants for necklaces out of our local fallen cedar trees and ...
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.
© 2015 Lady Bird Johnson Wildflower Center