There are two common diseases that cause  brown needles on Leyland Cypress, Seridium canker and Botrysphaeria canker.  Both diseases can cause the typical browning and die back of the needles.  In order to be certain what is wrong with your trees, I suggest that you have a certified arborist look at them.  A list of arborists that work in Chesterfield County can be found here.  This publication "Canker and Dieback Diseases of Leyland Cypress" gives a lot of information on these problems.

Unfortunately there is no treatment (no fungicide) that will successfully treat these cankers.

Pruning out the affected parts to include the canker on the branch is usually the only recourse available.  The arborist should be able to tell you if the trees can be saved.  

If you have additional questions on this subject, please use the reply feature within this email or call the Chesterfield Extension office at<personal data hidden>.
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