Mike Girdwain enjoys hiking in the woods.

But on a recent trip to McMahon Woods in Palos Township, the former Bridgeview resident had one of those experiences where you can’t see the forest for the trees — because the trees were no longer there.

A large area of the Cook County Forest Preserve District property southwest of 107th Street and 104th Avenue is practically devoid of vegetation. Dozens if not hundreds of trees have been cut down.

“It looks like clear-cutting out west,” Girdwain said.

The responsible party: a 21/2-inch long dragonfly.

The Hine’s emerald dragonfly has been on the federal endangered species list since 1995, and few areas have the elements conducive to its breeding. McMahon Woods is one of them, forest preserve district spokesman Steve Mayberry said, so the preserve is getting a makeover to accommodate the insect. Breeding areas are found only in northeastern Illinois, northern Michigan, Door County (Wis.) and Missouri.

Southlanders may recall that concerns over the same dragonfly delayed the south expansion of I-355 for several years. But the emerald-eyed insect isn’t all bad: It eats mosquitoes.

The trees at McMahon Woods were removed last month by the Army Corps of Engineers, Mayberry said. A $500,000 federal grant paid for the project, which actually is restoring the land to its natural state, Mayberry said.

Wayne Vanderploeg, an ecologist for the forest preserve district, understands Girdwain’s concerns about the trees. But he also understands the plight of an endangered species.

“This is a federally endangered species that only occurs in a few locations on the face of the Earth. This happens to be one of them,” Vanderploeg said. “They do their breeding here. It’s good for the dragonfly. What we are doing is enhancing the area.”

He said the natural drainage of water in the soil will create rivulets where dragonflies lay their eggs. Sand and gravel beneath the soil, left by glaciers millions of years ago, helps create the needed drainage, he said.

“These rivulets are what the dragonfly needs to survive. If the water does not percolate through the soil properly, the rivulets die, and so does the habitat and so does the dragonfly,” Vanderploeg said.

The downed trees that concerned Girdwain, who pointed out rings on large stumps that indicate the trees were perhaps 100 years old, shouldn’t have been there in the first place, Vanderploeg said. He said they began growing after farmers left the land about a century ago.

“In this case, (man) inhibited the natural process which had prevented trees being there in the first place,” he said.

Still, Girdwain, who now lives in Momence but returned to McMahon Woods because he liked the trees there, fears birds will be left without homes.

“It is true that we are reducing that particular habitat for birds,” Vanderploeg said. “But when you look at the whole picture, there’s a lot of habitat in the area.

“As land managers, our responsibility is to restore the habitat back to what it should be. We all agreed that this was the best approach.”

The watchdog group Friends of the Forest Preserves endorses the approach.

“Restoration in a forest preserve is all about helping a specific site to be in balance to provide the maximum habitat for a species,” executive director Benjamin Cox said Friday.

“This dragonfly has very special needs. A lot of things will grow anywhere, but certain things need the right, specific requirements to thrive. If this site is as healthy as it can be, I’m sure (the dragonfly) will do well.”

Nonetheless, Girdwain would prefer seeing tall stands of trees instead of barren land.

“I wonder how many other species will be endangered because of this,” he said. “What lengths do they go to to help one species at the cost of other species of animals and plants?”