Emerald Ash Borer

Emerald Ash borer (EAB) continues to spread throughout Milwaukee County and southeastern Wisconsin. This past year initial finds of EAB were confirmed in the following communities: St. Francis, Muskego, Hartford, Jackson and Slinger. As of February 2015, there has not been a confirmed detection in Whitefish Bay. In 2011, the Village Board approved an EAB Initiative to put in place a management strategy to best manage the Village’s public ash population through the EAB infestation period.

During 2011, 2012, 2013 and 2014 the Village removed approximately 882 ash trees and replanted 845 new trees of a diverse species mix.

In 2015, the Village will continue the ash reduction program with additional removals and continue replanting with multiple species. There currently are approximately 3,144 ash trees remaining in terrace areas along Village streets.

Prior to the implementation of our EAB Management Program in 2010, ash trees represented 46% of the total street tree population. After our 2015 ash removal and replacements are completed (approximately 280 trees), the ash tree population will represent 32% of the villages’ street tree population. The goal of our EAB Management Program is to reduce the ash population to a more manageable level of around 20% (1,900 ash trees) of the public tree population, while maintaining as much existing street tree canopy as feasible.

The primary component to maintaining this tree canopy is the chemical treatment of higher condition ash trees. In 2015, the Village will be continuing a second chemical protocol that began in 2014. Emamectin benzoate, commonly known as Tree-age, will again be used to treat trees that are 18 inches and larger diameter. Application will be by direct trunk injection into the root flare region of the trunk. This product is an ever other year application. For trees that are less than 18 inches in diameter, the soil injection process will again be utilized. This product requires annual treatment.

Treatment Program (Scheduled to begin in early April 2015)


The soil treatment process will begin in early April and continue for a number of weeks. Soil injected trees will be marked with a single small fluorescent green dot (on the street side) at the base of the tree.

The trunk treatment process will begin in early June and continue throughout the growing season. Trunk injected trees will be marked with two small fluorescent green dot (on the street side) at the base of the tree.

Approximately 1,050 ash trees will be marked for treatment in 2015 (PDF). Trunk injected trees that were treated in 2014 will not be treated again until 2016. Adjoining property owners of those public ash trees that will be treated can look for the green dot/dots on the street side at the base of the tree or click here for an address listing of those trees that will be treated.

Please note: Many properties have multiple ash trees in the terrace area and not all will be treated. In order to get the best distribution possible village-wide, some trees were bypassed in order to achieve the desired uniformity.

Black Dots on Trees


Village parkway trees that have a black dot on them (about 5 feet above grade, street side) are not at all related to our EAB Project. It simply means that the tree has been trimmed within the past couple of years as part of our tree maintenance program.