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?

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
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 09, 2009

From: Medina, OH
Region: Mid-Atlantic
Topic: Trees
Title: Browning of Red Western cedars in Medina, OH
Answered by: Barbara Medford

QUESTION:

I have a row of Red Western Cedars bordering my yard. One week after my lawn people but down spring fertilizer and grub control, they began turning brown. Is there any correlation? If not, what causes Red Westerns to have their branches turn brown? Thank you.

ANSWER:

Well, it would certainly arouse suspicions because of the time frame involved, wouldn't it? From our Native Plant Database, we learned that Thuja plicata (western red cedar), while native to North America (or it wouldn't be in our database) it is not native to Ohio. If you have had them for a while and they have been okay, the fact they are not native to your area is probably not the reason for the browning. 

So, we'll begin with the possibilities of the fertilizer and grub control. If the fertilizer was of the "weed and feed" type, and was sprayed around, that could very well be the source of the problem. "Weed and feed" fertilizer is specifically a lawn fertilizer. Grasses are monocots, and the weed killer in the fertilizer is aimed at dicots, or broad-leaved plants. So, what benefitted the grasses by killing off their competitors, the broad-leaved weeds in the lawn, could very well have done a lot of damage to the cedar. As for the grub control, we could find nothing about whether the ingredients in grub control were specifically a threat to plants, but, again, they contain certain toxic substances in order to kill the grubs, and if applied to tree foliage could likely cause trouble.

Other reasons for this browning? We learned that the western red cedar needs a moist, slightly acidic soil, but can adapt to a little more alkaline soil. It is susceptible to bagworm damage and heart rot, but neither are considered serious threats.

Conclusion? We don't have one. Again, the timing leads us to believe the spraying may be the cause. Whether or not the tree can recover, we don't know that, either. This is a valuable tree, and grows to be very large, but slowly. Give it some care, maybe some extra water, but not fertilizer, and hope that time will help the tree heal itself. Next time, either get a different landscaper or watch them closely. Untrained personnel often don't understand the consequences of what they are spraying around indiscriminately. 

Pictures of  Thuja plicata (western red cedar)

 

More Trees Questions

Spring blooming Acacia farnsiana in Austin
April 04, 2007 - I've been seeing a large shrub, possibly tree, around Austin this spring - and it is covered is small ball-like orangish-yellow blooms - very tightly covered in these blooms. From the car, it looks ...
view the full question and answer

What eats American holly bushes in winter?
January 24, 2010 - I live in Marlborough, MA and I was shoveling snow on January 19th and noticed how beautiful my Holly bush was covered in red berries against the new fallen snow. My husband said to me this morning (...
view the full question and answer

Transplanting a blue spruce from Pingee Grove IL
August 30, 2012 - Transplant 18" Blue spruce from 5 gal. bucket to ground.
view the full question and answer

Are poplar trees and willows safe for animals to eat
August 04, 2008 - poplar trees and willows, are they friendly for farm animals to consume leaves?
view the full question and answer

Suggestions for native perennials in Staten Island, NY
April 03, 2008 - My back yard garden has a good base of evergreen shrubs and perennials all doing well in clayish soil and I am ready now to add color and texture in an area with partial sun. Can you suggest hardy...
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.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center