Skip to main content

Pine Chlorosis: The Yellowing of Pine Trees

Post by Bob Mertens; Horticulture Program Specialist

We’ve been receiving numerous inquiries here at the Extension office regarding the yellowing (chlorosis) and subsequent deaths of native Florida slash pines, most notably in and around urban landscapes.   The blame often wrongly falls on bark beetles or a newly introduced disease.  The actual cause of this pine chlorosis however is a bit more complex.

Slash pines are native to acidic soils and tend to do poorly in high pH alkaline soils or when exposed to alkaline irrigation water.  In new developments, fill soils usually have a high pH.  In addition, root injury during construction and soil added above the grade of existing trees are often the cause of pine chlorosis.  Symptoms can frequently take years to appear and are often not connected by homeowners to the original damage.  Stressed trees can attract borers and bark beetles which are generally blamed for the problem.

Landscape maintenance practices can also be the cause of pine chlorosis.  Well-fertilized lawns maintained over the root zones of pines are frequently to blame.  This problem can often be prevented by maintaining mulched areas beneath the canopies of pines and by avoiding the use of alkaline irrigation water over the root zones.

phone: 941-861-9805                  email:

Further information regarding pine chlorosis is available at the following website:


3 Comments on “Pine Chlorosis: The Yellowing of Pine Trees

  1. Kevin
    I just ran across your blog reading through the IFAS website. I was hoping to make contact with you. We ( TREES and Turf Inc. ) have been treating yellowing Slash Pine for years in Florida. I have some great before and after pictures of the declining trees restored. Our business is based on the monitoring and treatment of urban trees. I am a certified arborist and have been working in the tree industry 13 years. It would be great to have your contact and introduce myself. I can be reached at 651-777-4417

    • Good morning, Chase. I’ve copied your comment and forwarded it to our commercial and residential horticulture agents: Marguerite Beckford and Dr. Pat Williams, respectively. Your work sounds like a great fit for what they bring to the community. Best, Kevin