TERRE HAUTE —
The effects of the emerald ash borer on ash trees in Terre Haute is accelerating, Indiana State University’s grounds manager says.
ISU is in its third year of chemically treating and removing trees infected by the emerald green colored beetle, first discovered near Detroit, Mich., in 2002. The borer, native to Asia, likely arrived in the U.S. in wood packing materials in cargo ships or airplanes.
“Our guideline that we are using is once an ash tree is 50 percent gone, we have to remove that tree because of risk associated with high pedestrian traffic under the trees or parked cars,” said Stephanie Krull of ISU.
The university is in the midst of removing 15 ash trees on campus, and it has chemically treated 180 of its 450 ash trees.
“We have roughly lost 70 to 80 trees of the [270 trees] that have not been treated,” Krull said.
“It is definitely accelerating, and the worse part is still coming,” Krull added. “At some point it will peak, and we will see the insects flying around, but that definitely didn’t happen this year.”
Krull said treated trees are doing well, “but not at the 95 percent rate like research was publishing, but I think that is due to other conditions such as the drought in 2012,” Krull said.
The effects of the emerald ash borer can be seen in a busy section of Terre Haute, around the Olive Garden restaurant, said Sheryle Dell, Terre Haute city forester.
“We are seeing the EAB is hitting some areas pretty hard,” Dell said, including along Wabash Avenue, Ohio Boulevard and in the northern section of the city, such as near Coy Park on North 16th Street.
The city last year treated almost 300 ash trees, but “we have not treated anything this year. We don’t have the manpower” nor budget to treat additional ash trees, the city forester said.
The city has removed fewer than 50 ash trees this year “but way more need to come out,” Dell said. Dell said the EAB will have an impact on some city subdivisions, such as Dobbs Glen, where ash trees compose 80 percent of the trees.
However, the EAB is not as high on Dell’s list this year. Ash trees compose about 7 percent of the city’s 17,000 trees in public right-of-way, not including trees in city-owned parks.
“We are not as pro-active on [ash tree] removals right now because so many of our other street trees, predominantly maple trees, are just dying,” Dell said. “So I have greater hazard right now.
“We have spent over $80,000 on tree removal so far, and I have another 50 sitting here and another 100 I have not looked at yet. Not all of those will be removed, but as far as the tree canopy, we are in a crisis situation,” Dell said.
“It is because we an aged population of trees that just naturally die, and they are urban street trees that have never been maintained,” the forester said.
Dell said 40 percent of the city’s tree canopy are maple trees, planted in the 1930s or earlier.
Other factors include environmental issues such as 2012’s drought. Other trees, such as tulip poplars, were hit in 2012 by an insect named the tuliptree scale. Attacked trees rained a sticky mess of an insect waste product called honeydew.
Urban trees also face other factors such as small growing areas, surrounded with concrete and cars, Dell said. “The areas that trees are planted aren’t large enough for them to live to maturity. We plant trees in narrow tree rows that are less than 5 feet” wide, the city forester said.
“It is a really desperate situation, and our [city tree] canopy is going to change,” Dell said. “Also, in the city parks, there is no maintenance. There again, there are old trees, and there is not a replanting program, and there is not a removal program,” Dell said.
Property managed by the Vigo County Parks and Recreation Department has not yet seen the damaging effects of the ash borer, said Adam Grossman, assistant park superintendent.
The park department chemically treated less than 145 trees this year at Fowler Park’s campground canopy, he said. “To my knowledge, Fowler Park does not yet have EAB in it yet,” Grossman said. “We have cut down a couple of ash trees, including a big one, struck by lightning. I inspected the top of the trees where EAB starts and saw no sign of EAB, or in any of our parks.”
Still, Grossman will continue a chemical treatment of about 60 ash trees in Prairie Creek Park and Hawthorn Park next year in a measure to reduce the impact of the beetle on ash trees in the county parks.
Reporter Howard Greninger can be reached at 812-231-4204 or email@example.com.