Rent Shop Volunteer Join

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 01, 2010

From: Hillsboro, OR
Region: Northwest
Topic: Diseases and Disorders, Trees
Title: Why are my lemon Cyprees trees turning Black?
Answered by: Jimmy Mills

QUESTION:

I have 3 lemon Cypress plants - all are about 6 feet tall. One of them has started turning black on one side - like it's been burnt. The inside of the plant is also turning black. I assume something is eating it from the inside out. What can I do to stop it?

ANSWER:

Lemon Cypress is a cultivar called Goldcrest or Golden Crest of  Cupressus macrocarpa (Monterey cypress). This link from Floridata provides general information about the plant.

The TopiaryShop recommends checking your plants for aphids. They secrete a substance called honeydew which can give the plant a black sooty appearance from sooty mold growing on the honeydew.

It is difficult for us to diagnose plant diseases from a distance, so I'm going to suggest that you contact the folks at the Washington County Office of the Oregon State University Extension Service for some help closer to home.

 

 

More Diseases and Disorders Questions

Can a Quaking aspen grow in central Texas?
August 11, 2015 - I live in Austin and like the idea of a Quaking Aspen tree. I live on a creek and the tree(s) would get good sun and water. Am I crazy?
view the full question and answer

What is the black stuff growing on my thoroughwort?
October 27, 2015 - What is the black stuff on my thoroughwort plant's leaves that is killing the plant?
view the full question and answer

Oak roots damaged by ax from Austin
July 03, 2013 - Hello. I am attempting to create my own tiny copy of the Wildflower Center within my yard. I'm using all native, drought tolerant plants. My front yard is full of live oaks. I used a sod cutter la...
view the full question and answer

Dying non-native St. Augustine grass from Austin
May 02, 2013 - Although we all know St. Augustine grass is not a good thing, I am stuck with it and am trying to save areas that appear to have take-all fungus. I have done much reading online and have tried peat m...
view the full question and answer

Location of Alamo fungicide kit from Georgetown TX
July 03, 2012 - Where can I buy the Alamo fungicide injection kit shown in the oak wilt video?
view the full question and answer

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