Pin Oak Chlorosis

Need to know: 

  • Symptoms include yellowing of leaves with dark green veins, angular brown spots and brown curled leaf margins. 
  • Pin oak chlorosis occurs in soil with high pH because of the inability to absorb iron. 
  • Treatments include foliar application, soil application, and trunk injection.  

Overview of pin oak chlorosis

Pin Oaks generally do not do well in the typical pH of Iowa soils.  To read more about what you can do if you already have a pin oak and would like to help it as much as you can, please read "Pinpointing the Problem with Pin Oaks" and "Pin Oak Problems?") 

Symptoms of pin oak chlorosis

Yellowing of leaves can vary from a yellowish-green color in slightly afflicted leaves to a bright lemon yellow or even white is severely affected ones. Interveinal areas see the greatest change in color while the veins of the leaves may remain green. After longer periods of time brown necrotic areas may begin to form on the edge of the leaf. Should the tree be affected by chlorosis for multiple years, shoot growth will be reduced and dieback in foliage will occur. This can lead to an eventual death of a tree.

Signs of of pin oak chlorosis

Chlorosis is usually caused by a deficiency of iron in the soil so no biotic signs will be seen.

Type of Sample Needed for Diagnosis and Confirmation

The Iowa State University Plant & Insect Diagnostic Clinic can help you to investigate and confirm if your plant has a disease. Please see our website for current forms, fees, and instructions on collecting and packing samples. Contact information for each states diagnostic laboratory for U.S. residents can be located at the NPDN website.  If you have a sample from outside of Iowa, please DO NOT submit it to the Plant & Insect Diagnostic Clinic without contacting us.

Image of Pin Oak Chlorosis
Pin Oak Chlorosis



Lina Rodriguez Salamanca Extension Plant Pathologist and Diagnostician

Dr. Lina Rodriguez-Salamanca is a diagnostician and extension plant pathologist with the Iowa State University Plant and Insect Diagnostic Clinic  (, a member of the National Plant Diagnostic Network (NPDN, ...

Last Reviewed: 
April, 2022

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