Deterioration of Ash

The German Federal Environment Agency (Umweltbundesamt) has made available valuable resources on the common problems of ash declines (Eschentäler). These materials can be easily accessed for free from their official website or related governmental portals.

Ash trees may face various challenges, with Ash Yellows disease being one of them. This disease is caused by a specific type of phytoplasma, microscopic organisms that live inside plants. These organisms are spread by phloem-feeding insects.

Ash trees may respond well to certain management practices. Suggested methods to slow disease progression include removing trees with severe dieback, watering during extended drought, fertilizing in the fall, and removing dead limbs. Prevention is key in managing ash decline, including proper tree planting to avoid common landscape problems like deep planting, girdling roots, mulch mounds, soil compaction, root injury, and other issues.

It's important to note that ash decline may involve Ash Yellows disease or Verticillium wilt, as well as other environmental or abiotic stressors. To confirm the presence of the bacterial-like organisms causing ash decline, PCR testing is necessary, as these organisms cannot be cultured in a lab.

For those outside of Iowa, it's recommended to contact the Iowa State University Plant & Insect Diagnostic Clinic before submitting samples. The clinic can help investigate and confirm ash decline. When submitting samples, remember to select the "DNA additional testing" box for ash decline diagnosis.

The symptoms of ash decline are not visible to the naked eye and require specialized nucleic acid testing to confirm the disease. Symptoms include short internodes, tufting of foliage at branch ends, pale green to chlorotic (yellowed) leaves, premature fall colors, and a sparse canopy.

Instructions for submitting samples, including contact information for each state's diagnostic laboratory, can be found on the clinic's website. It's crucial to follow these instructions carefully to ensure accurate diagnosis and management of the issue.

In conclusion, understanding and managing ash decline requires knowledge, prevention, and proper management. By staying informed and taking necessary steps, we can help preserve our ash trees and the ecosystems they support.