Treatment for Lealand Cypress Trees

Asked July 18, 2020, 11:22 AM EDT

I have a Lealand Cypress Tree, about 10 years old that is beginning to show branches turning brown, perhaps dying. Can you recommend a treatment to save the tree? Thank you John

Somerset County Maryland

1 Response

There could be several reasons for brown branches and or dieback. You can send us photos of the whole tree, around the base of the tree, and affected branches so we can see what you are dealing with. Below is more information.

We are hearing of many problems and declines of leyland cypress, which begin to show up at the 15-20 year mark. They are not really well suited to our climate long term. Stresses such as winter injury, too much shade, planting too deeply, etc.)
can lead to disease and insect (bagworms) issues.

Here is more information, from our Maryland Grows blog recently written by our plant pathologist:
https://extension.umd.edu/hgic/topics/why-are-leyland-cypress-trees-turning-brown

and the diseases most prevalent: https://extension.umd.edu/hgic/topics/seiridium-and-botryosphaeria-canker-leylands-trees

All you can do is prune out dead branches during dry weather. Keep watered during dry periods and make sure mulch is no thicker than several inches and keep away from the base of the trunk.

Marian