Crews from Commonwealth Edison sprayed chemical poisons in two areas of Evanston recently to kill vegetation – including some sizeable trees – under the tall power lines that bisect central Evanston northeast to southwest. One area was north of Church Street; the other, between Church and Lake streets.

The crews used the herbicide Garlon 3A to kill “invasive species” and other vegetation that potentially could harm the electricity-bearing wires, said Jeff Burdick, spokesperson for Commonwealth Edison. The chemical, he said, is approved by both the Environmental Protection Agency and OSHA. He said Garlon 3 is probably similar to many over-the-counter herbicides. In addition, he said, “We use a state-licensed operator to apply the chemical in a targeted way so that it stays on our property [the right-of-way of the power lines].”

ComEd must keep the area around power lines clear to prevent interruptions in power, Mr. Burdick said, as well as to avoid fines for not doing so. The tall structures along the berm hold transmission lines, he said, which carry more electricity than do the smaller distribution lines found in residential areas. A power interruption from one of these towers could cause loss of service to “millions of customers,” he said.

Mr. Burdick emphasized ComEd’s right and duty to destroy vegetation that could either grow to a height that could harm the wires or become so dense as to harbor wildlife that could harm them. He said, though, that he did not believe ComEd crews had destroyed any trees, discounting buckthorn as an “invasive species” and saying that some saplings might have been destroyed.

Paul D’Agostino, superintendent of Parks/Forestry for the City, said several trees in both areas, some as tall as 15 or 20 feet, had been destroyed. He also said he was surprised that the City had not been notified of ComEd’s plans.

Mr. Burdick said generally ComEd is in “close contact” when they are managing vegetation around the distribution lines. “It’s still our property,” he said, “but we will be more proactive [about notification].”

He added, “ComEd tries not to make its vegetation-management practices ‘either/or’ – either you have electricity or you have nice vegetation. We try to work with municipalities. If we remove something, we replace it.”

By the end of last week, ComEd had removed many of the dead trees. The company says it plans to replace the dead trees, grasses and bushes with a mix of prairie flowers and grasses. “Their hope is to establish the prairie mix to prevent the trees from growing back. This will cut back on future maintenance, requiring only mowing a few times each year,” said Mr. D’Agostino.

Mr. Burdick said he believed Garlon 3A “will not affect the ability to grow grass in that area next month.”

Mr. D’Agostino said, “I think a prairie establishment on an embankment is perfect – it reduces erosion and takes minimal maintenance once it’s established. It could eventually be similar to the site along Green Bay Road north of Central Street.”