Tree decline

Encyclopedia Article

Image of declined tree in urban area
Declining trees are a common sight in the urban environment.

Overview of decline 

A gradual decline in health is a common problem for many trees in urban and rural areas across Iowa.

Signs and symptoms of decline 

Symptoms may include stunted growth, premature leaf drop, late spring leaf developments, sparse foliage, light green or yellow foliage, twig and branch die-back, or many other abnormal symptoms.

Disease cycle of decline 

Usually, there is no single reason for tree decline.  Often, a combination of factors reduces a tree's vigor, and stress on a tree can make it vulnerable to additional problems.  Disease and insects often capitalize on the tree's low vigor and accelerate its decline.

Type of Sample Needed for Diagnosis and Confirmation

The Iowa State University Plant & Insect Diagnostic Clinic can help you to investigate and confirm if you plant has this 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.  If your sample is from outside of Iowa please do not submit it to the Plant & Insect Diagnostic Clinic without contacting us

Management of decline 

For information on tree decline please see handout Understanding Decline in Trees" from Iowa State University Extension.