YOUR COUNTY: Preparing for arrival of the deadly emerald ash borer by Jim Baumgart

It has begun. Death is beginning to stalk the American white, green, pumpkin, black and other native ash trees by the emerald ash borer.

When the beetle arrives in Sheboygan County, and it is already in a neighboring county, the slow process will begin – tree by tree until most are likely dead. The same thing happened to the American elm and, much earlier, American chestnut when they became infected.

The insect was first found in 2002 in southeastern Michigan, but is believed to have arrived in the early 1990s before it was identified.

Emerald ash borer is a non-native wood-boring insect that feeds on ash trees. It is native to Asia, in particular northeast China, Korea, Japan, Taiwan, and a small area adjacent to Russia and Mongolia. In its native range it feeds on a variety of plant species and is only considered a minor pest. Asian trees have developed a resistance, and it has predators and pathogens that keep it in check. But North American ash trees have no natural resistance and few predators. Once it reaches a native ash tree, the tree will eventually die.

One should understand that only the genus Fraxinus, including green ash, white ash, black ash, pumpkin ash and other native species in the same genus, are affected. Mountain ash is not a true ash and is not affected.

To date, it is reported that the emerald ash borer has killed 15 million ash trees in a 20-county area around Detroit and has been found in 14 states and Ontario. The Wisconsin Department of Agriculture, Trade and Consumer Protection announced in August 2008 that the emerald ash borer had been found in the village of Newburg, Ozaukee County. Since then, it has been found in Brown, Crawford, Milwaukee and Vernon counties.

With the emerald ash borer found so close to Sheboygan County and with the great impact it could likely have on communities, a Sheboygan County Emerald Ash Borer Work Group, consisting of representatives from state, county, city, village and town levels, was formed in spring 2009 to find the best way to plan for the impact of the beetle in Sheboygan County.

With the leadership of Sheboygan County and funding ($15,000) from a Sheboygan County Stewardship Grant, an inventory of public trees was done as the first step in developing a plan of action. The inventory covered all public trees in the county and included 18 municipalities. Nearly 30,000 trees were inventoried and showed that 23 percent of the trees were ash.

Sheboygan County Land and Water Conservation Department applied and received a 2010 Wisconsin DNR Urban Forestry Grant for $5,000 to develop the Emerald Ash Borer Resources Management Plan for Sheboygan County Communities. That plan has been completed and includes a host of information that will be valuable, including maps showing location of all ash trees in their local communities on public lands and right of ways.

Ash trees in the larger parks, backyards, or private lands away from roads were not surveyed. Private lands in rural Sheboygan County were also not surveyed, but according to a United States Department of Agriculture Service forest inventory and analysis for Sheboygan County, it is estimated that Sheboygan County has some 10,675,000 ash trees (including many small-diameter trees).

Why is it important to have a plan in place?

The cost of tree removal could be great. Possible use or sale of the wood could be beneficial. Also of concern is loss of urban shade trees, which save on summer air conditioning and winter heating, and much more.

Next week: More on the Emerald Ash Borer Resources Management Plan for Sheboygan County Communities.