EAB for the Master Gardener - Pesticides

Table 1: Possible Actions Based on the Relative Value of Ash Trees in Landscape Settings

Low value¹ ash trees

• Intersperse NS⁴ replacement trees with ash to establish and grow before ash trees die.
• Cull out ash in poor condition.

• Allow non-hazardous trees to die and fall. Remove potentially hazardous ash before they fall.
• Replace dead ash with NS trees.

Moderate value² ash trees

• Intersperse NS replacement trees with ash to establish and grow before ash trees die.
• Begin appropriate pesticide treatment.

• Continue pesticide treatments on yearly basis until NS replacement trees are of adequate size.
• Remove ash as needed after discontinuing pesticide treatment.

High value³ ash trees

• Maintain or improve vigor of high value ash.
• Begin appropriate pesticide treatment.

• Access condition and value of chemically protected ash trees yearly.
• Repeat pesticide treatment on vigorous trees yearly.

¹ Low value ash trees: ones that are not integral to the landscape and that the owner does not wish to invest resources in to protect chemically. Also, includes ash in poor conditions for any reason.

² Moderate value ash trees: ones that the owner wishes to keep alive until NS replacement trees are large enough to provide benefit.

³ High value ash trees: ones that are important to the landscape and in which the owner is willing to invest resources on a yearly basis. Trees must be in good condition initially.

⁴ NS: non-susceptible, site appropriate species of trees