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

Monday - October 12, 2009

From: Hillsboro, OR
Region: Northwest
Topic: Diseases and Disorders
Title: Brown dead spots on arborvitae in Hillsboro OR
Answered by: Barbara Medford

QUESTION:

Hello. I live in Hillsboro, OR and have several mature arborvitae as a privacy screen in my backyard. They are on our side of a black chainlink fence separating our yard from a drainage area maintained by the city. Early last week we noticed that there were dead patches on all of the trees in our surrounding area. They are dead patches and not "dying". Apart from these dead patches, the trees seem healthy. This is inter-species as it seems to have affected pines, deciduous, broadleaves, etc. At first we thought it was just an irresponsible pesticide/herbicide job, but the dead patches are becoming worse and more noticeable and cover quite a large area. It has affected the trees in our small backyard, all of the trees in the drainage area, and across the street from that. Is there anything you know of that could possibly cause this?

ANSWER:

Sadly, you may be right about herbicide damage. Land maintained by a public entity, such as a city or county, may be sprayed for weeds, often by sub-contractors. If this is done carelessly or by untrained operators, the slightest puff of wind or bad aim can damage or kill other plants around it. The first step you should take is to call the city office responsible for maintaining that drainage area, and inquire about what has been done there recently. Certainly, you want to go to the drainage area and see if damage appears in the grasses or weeds in that area. Another thing to think about when you contact the city is that indiscriminate spraying of herbicide or pesticide, especially in a drainage area, can result in those poisons entering lakes in the area and, eventually, your glass of water.

Since this appears to be affecting more than one species of plant, if you eliminate the possibility of herbicide, we would recommend you contact the Oregon State University Extension Office for Washington County.  If this is happening in your neighborhood, it is happening in others and the Extension people are closer to the problem, and may be able to help you find a solution. 

 

More Diseases and Disorders Questions

Care of Styphnolobium affine, Eves necklace
October 05, 2007 - I have an 18 yr old Eve's Necklace tree that is dying from the "bottom up". It has only a few leaves at the very top of the tree. I have, connected to the gutter, a rain barrel from which the exc...
view the full question and answer

Oak tree with browning leaves in Brenham TX
August 16, 2011 - I have a large oak tree in my small back yard. I also have a sprinkler so the tree has been receiving some water. Nevertheless, some of the leaves are turning brown in patches. Would drip watering ...
view the full question and answer

Problems with Eastern hemlock in Greenville SC
July 02, 2009 - Dear Mr. Smarty Plants, I have a beautiful, young, 5 and a half foot tall Eastern Hemlock. I purchased and planted it two years ago in the fall. It has been doing very well all this spring. And ne...
view the full question and answer

Green cyst-like growths on Texas persimmon leaves
September 20, 2013 - We have a mature Texas persimmon. We just noticed some green cyst-like growths on the tops of some of the leaves. The undersides of those leaves have black spots where the growths are. They looks like...
view the full question and answer

Identification of worm feeding on chockecheery
August 03, 2007 - I am looking to find out what sort of worm looking insect, is commonly found on chokecherry trees. It has a turquoise appearance with yellow fingerlike projections on the back. It suctions onto the ...
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 | STAFF
© 2015 Lady Bird Johnson Wildflower Center