Emerald Ash Borer - Current Thoughts On Management

Current Thoughts On Management

The first step in any management plan is to take inventory of what you have. This is done by either doing a formal tree inventory, or through a more basic counting and measuring of trees. Each tree should receive a rating - there is a scale that is used by some cities that assigns a number to each tree based on condition, location, age, value, and density. A low score of 1 would be assigned to Ash that are hazardous and potentially dangerous. The highest rating would be a 5 for specimen or heritage trees.

The fact that there are now effective, low cost treatments, changes how ash trees are managed in two very important ways. It allows cities to save trees far more cost effectively then removal and replanting new trees, and preserves the important tree canopy. This allows removal and replanting cost to be spread over time by providing for the opportunity of a slow transition of the ash trees out of the urban forest. Treatment can also be used to stage trees that are slated to be removed in the future, thus allowing the city to remove trees as they choose, instead of being forced to remove all their ash trees over a few years. There is a value calculator for urban trees created by Purdue University, http://extension.entm.purdue.edu/treecomputer/. This can help determine what trees are worth to a city or neighborhood, and is useful in determining which trees should be removed /replaced, and which trees are worth saving.

Implementation of the management plan should begin with removing the hazardous and weak trees. This can be started immediately and is a good idea even if the Emerald Ash Borer has not arrived yet. The most effective method to monitor for the Emerald ash borer is to utilize a purple trap. Once the insect is found - begin treating the trees you intend to save as well as the trees you want to stage for removal. Trees treated with insecticide will slow down the borers population build up.