Pierre lost 40 trees to Dutch elm disease in 2012 at final count, several times as many as in recent years, and foresters say the continuing drought may have been a contributing cause.
Pierre Superintendent of Parks Todd Kelly said the 40 trees removed from city property in 2012 compares with seven trees diagnosed in all of 2011, 11 in 2010, 12 in 2009, and 17 in 2008. The toll was higher in the 1980s and early ‘90s, Kelly said, when the city was removing from 50 to 100 trees each year, but the 2012 count was the highest the city has seen in years.
That’s all the more astonishing because there simply aren’t as many American elms left to get sick.
Parks and recreation director Tom Farnsworth said the fact that trees went for months without rainfall was probably a factor.
“The trees on the boulevard weren’t getting as much water as they normally would,” he said.
Stress is a big factor, agreed Dan McCormick, chairman of Pierre’s Arbor Board.
Three different kinds of beetle – the European elm bark beetle, the banded elm bark beetle and the native elm bark beetle – spread the fungus that causes the disease. It can also be spread by roots of healthy and diseased trees touching underground. And a homeowner who trims a sick tree and uses the same tool on a healthy tree without cleaning it with a household bleach solution can also spread the disease.
McCormick said in 2013 the city’s big tree-planting projects will include re-planting trees that were lost around the softball complex, planting more trees in the arboretum, and possibly planting some trees along the new Fourth Street walking trail.