Following the mild winter and unseasonably early spring weather, the Emerald Ash Borer has been spreading at a rapid pace, leading to the removal of a large number of Evanston’s parkway trees. In July 2006, the Illinois Department of Agriculture (IDOA) confirmed the Emerald Ash Borer (EAB) was located in the far northern edge of Evanston. When the insect was first detected, Evanston had over 4,000 ash trees on its parkways and in its parks, which was about 12% of the City’s 33,000 public trees.

The EAB has now spread to nearly every corner of the city. While there continues to be efforts to find a control measure to stop the spread of the invasive insect, nothing has yet proven to be effective enough for the City to consider widespread use. The Forestry Division’s only real option at this time is to quickly remove any ash trees that Forestry staff has confirmed as infested. As a result, the number of parkway ash trees removed over the past year (nearly 500) has outpaced the funds to replace them. Staff anticipates that this insect will continue to spread at a rapid pace.

In some cases, when the infestation is not severe, the Forestry Division has allowed residents to treat their ash trees on the parkway. It requires their contractor to use Tree-Age (which cannot be applied by a homeowner because it is a restricted use product) and to get a permit to do so. Forestry Division staff will inspect the Ash to be sure it is a good candidate for injection, and then issue the permit accordingly.

Ash trees had been widely planted in the city and in much of northeast Illinois because they were fairly inexpensive and generally quite tolerant of soils and climate in this area. In the early 1970s, a master tree planting plan was implemented that assigned each separate block of the city with one specific tree species. The unintended consequence of this plan is that those blocks designated to be planted with only ash trees are now being stripped of nearly all their trees. Some blocks have even been entirely cleared of all parkway trees.

Specific examples of blocks that recently have been severely affected by ash removals include the 100 and 500/600 blocks of Asbury, 2100 block of Ashland, 2900 block of Colfax, 1700-1900 blocks of Darrow, 600-800 blocks of Dempster, 1100/1200 and 1700/1800 blocks of Dodge, 900 block of Elmwood, 2200 block of Ewing, 2700 block of Hartzell, 1900 block of Jackson, 1500/1600 blocks of McDaniel, 700/800 blocks of Oakton, 2200/2300 blocks of Ridge, 300-500 blocks of Sherman, and the 3000 block of Simpson.

The plan going forward, especially for those blocks that have been especially hard hit, is to replace one-third of the trees either this spring or fall, and then continue replacing one-third in 2013 and 2014.

A reforestation fund was established in 2011 following a series of severe storms that destroyed many of Evanston’s public trees. Donations to this fund will be used to more quickly replace Evanston’s urban forest. Forms are available online at www.cityofevanston.org/forestry. For more information, please visit www.cityofevanston.org/forestry or call 3-1-1.