Chlorosis Management

Introduction to Chlorosis

Chlorosis is a condition where a tree is not able to produce adequate chlorophyll (the green, photosynthetic pigment in leaf tissue).  This inhibition of chlorophyll production causes the leaf tissue to gradually turn yellow. As photosynthetic food production decreases, the tree eventually cannot carry out normal processes and functions. This adversely affects tree health and can lead to eventual mortality (when chronic), or other opportunistic pest and disease attack.

Causes of Chlorosis

Chlorosis is often the result of iron or manganese deficiency, usually closely linked to soil pH (alkalinity). Nutrients may be present in adequate amounts in the soil profile, but are unavailable for tree use due to a higher (more alkaline) soil pH.  Ideal soil pH for most trees is 5.5-6.5, or slightly acidic.  Other factors, frequently in combination with nutrient deficiency and soil pH, can also contribute to the presentation of chlorosis. Soil compaction and poor drainage are often compounding factors to more severe presentation, as are drought conditions during summer months.

A number of Wisconsin’s native shade trees are prone to becoming chlorotic when presented with site factors that predispose the condition. White Oak, Pin Oak, Red Maple, and River Birch are considered more susceptible deciduous trees. White Pine is one evergreen susceptible to Chrlorosis.

Chlorosis Treatment Plan