DiseaseHigh Severity

Ash Yellows

Phytoplasma (formerly mycoplasma)

A phytoplasma disease that affects ash species throughout northeastern and midwestern North America. The disease causes progressive decline with reduced growth, abnormal branching patterns, and eventual tree death.

Peak Season: Symptoms develop gradually over multiple growing seasons. Most apparent during growing season when foliage symptoms are visible.
View Treatment OptionsRecommended Products
Ash yellows symptoms showing characteristic crown dieback and yellowing foliage

Identification & Symptoms

What to Look For

Reduced growth and vigor
Deliquescent (abnormal) branching patterns
Witches brooms formation
Progressive decline over several years
Chlorosis (yellowing) of foliage
Stunted growth
Branch dieback
Root loss and tree death

Potential Damage

Progressive root loss leading to decline
Reduced photosynthetic capacity
Abnormal growth patterns
Branch dieback and tree mortality
Increased susceptibility to other stresses
Complete tree death in severe cases

Lifecycle

Phytoplasmas move through sieve cells in the phloem, causing death of inner bark. The pathogen is transmitted by leafhoppers that feed on infected trees. Symptoms may develop up to 3 years after phytoplasma is detected in ash phloem.

Professional Treatment Approach

1

No cure available once infected

2

Remove severely infected trees

3

Maintain tree vigor to improve tolerance

4

Manage environmental stress factors

5

Control leafhopper populations when possible

6

Plant resistant species in affected areas

Recommended Mauget Products

Vigor-53

Professional-grade treatment specifically effective against ash yellows.

View Product Details

Inject-A-Min Iron/Zinc

Professional-grade treatment specifically effective against ash yellows.

View Product Details

Stemix Plus

Professional-grade treatment specifically effective against ash yellows.

View Product Details

Need Professional Diagnosis?

Our certified arborists can help you accurately identify tree problems and develop an effective treatment plan using Mauget's proven injection systems.

Schedule ConsultationUse Diagnostic Tool