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

Tuesday - September 12, 2006

From: Pasadena, MD
Region: Mid-Atlantic
Topic: Diseases and Disorders, Trees
Title: Yellowing of Thuja occidentalis leaves in early Fall in Maryland
Answered by: Joe Marcus

QUESTION:

Mr. Smarty Plants, I am from Maryland. Please help. I have planted 23 Thuja occidentalis Smaragd in my front yard a few months ago. Height of about 3 feet. Most of the trees have turned golden brown. Are they dead? or is that normal. What did I do wrong? They are suppose to be evergreens. Thanks Bonita

ANSWER:

Thuja occidentalis or arborvitae is an evergreen species. While it is normal of arborvitae - especially certain cultivars - to turn reddish-yellow during winter months, it is not normal for that to happen this time of year.

Some possible causes for your plants' condition are water stress (too much or too little), root disease which is usually related to watering issues, transplant shock, leaf miners or mites. From your description of your plants we would say that leaf miners and mites are not the likely culprits, but we can't rule them out. More likely, there is some issue involved in the transplanting and acclimation process that caused you plants to turn brown.

You should talk to your local nurseryman, arborist or cooperative extension service about the problem as someone may need to actually see your plants to give you a proper diagnosis. You are fortunate in the state of Maryland to have an excellent cooperative extension service. Their really nice Home and Garden Information Center website provides information for investigating plant problems.

 

More Trees Questions

The perfect tree for San Rafael CA
November 10, 2009 - Want to plant a tree that is slow growing and has shallow root system that won't lift the concrete, that does not shed, and is green throughout the year.
view the full question and answer

Replacing a Mexican ash with a live oak in Rockport TX
April 25, 2010 - I live in the Texas Coastal Bend (Rockport, TX). I recently lost a huge Mexican Ash, probably 45 years old. The trunk measures 11'6" at ground level, and gets progressively larger from there up. Its...
view the full question and answer

Landscaping plant for Austin
September 01, 2011 - Great site! Have gotten lots of ideas. We're about to start construction on a fairly major landscaping project: raised beds/privacy screen. We're at the top of a hill in the Hill Country just wes...
view the full question and answer

Tall privacy hedge in Fort Worth, Texas
January 15, 2010 - I need a fast growing plant that reaches a height of 14 to 16 feet suitable as a privacy hedge. Prefer minimal maintenance and disease resistant. I have a 3 story condo being built behind my home in...
view the full question and answer

Privacy Screen for Heavy Clay and Full Sun in Louisiana
April 19, 2013 - What would be a fast-growing plant for privacy in Louisiana? I have heavy clay and full sun.
view the full question and answer

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