Host an Event Volunteer Join Tickets

Support the plant database you love!

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 - April 14, 2011

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

QUESTION:

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.

ANSWER:

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

Does Chilopsis linearis, var.Bubba produce seed pods? No.
October 01, 2007 - We have a really beautiful 2-year old Bubba, Desert Willow. It is already about 12 feet tall. I really have two questions. One does the Bubba form the seed pods like the other types of Desert Willows?...
view the full question and answer

My newly planted Mountain Laurel isn\'t doing well.
March 13, 2009 - My mountain laurel was planted from a container in Dec. It is in part sun, clay soil, and its leaves are turning yellow. should I move it or will that kill it?
view the full question and answer

Distance of oak tree to existing driveway in San Antonio
July 07, 2009 - How close can I plant a live oak tree (15 gal) next to an existing driveway. I have about 3 feet space to plant between a fence and a driveway. This is the best spot to provide future shade. My concer...
view the full question and answer

Will non-native and invasive Mexican petunias grow under oak trees from St. Augustine FL
March 24, 2013 - Will Mexican Petunias grow under an Oak tree?
view the full question and answer

Shade Tree for Sunny California Yard
April 03, 2015 - I am getting ready to sell my home in Van Nuys, California. My home had a beautiful fruitless mulberry that had to be removed. My front door faces west. The house is now very hot. I would like to know...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.