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 Diseases and Disorders Questions

Problems with mountain laurel from Sunrise Beach TX
August 29, 2012 - In Llano Co., TX near lake LBJ, crushed granite type soil - my 4 - 5 year old TX Mtn. Laurels (2), about the size of large wheel barrows, are turning very pale, dropping leaves and on 1 the seed pods ...
view the full question and answer

Leaves wrinkling on Tecoma stans from San Antonio TX
August 16, 2013 - My two year old esperanza (planted in the ground) froze back last winter, came back from the roots & has been doing well all summer. Recently one branch has leaves that are nice & green but very wrin...
view the full question and answer

Native firebush dying in Sun City Center FL
July 17, 2009 - I have a native firebush, it is suddenly dying branch by branch, from the inside out, I have noticed odd things look like wasps but with speckled wings on it. What could be killing it. The inside bra...
view the full question and answer

Transplant shock in Vacccinum corymbosum (highbush blueberry)
June 28, 2007 - Blueberry plants - We planted Northland and Blue Crop, 2 of each. All 4 plants have some leaves that are turning brown. This starts at the tip of the leaf, eventually encompasses the entire leaf, a...
view the full question and answer

Recovery of water-stressed Agarita
August 11, 2014 - Hello! I planted a small agarita at the end of May and then left town for six weeks. During that time it was supposed to receive weekly deep irrigations to help it establish, but it seems that som...
view the full question and answer

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