SHORT HILLS, N.J. (CBSNewYork) – The observation hive at the Cora Hartshorn Arboretum in Short Hills, New Jersey is buzzing with activity, as the surviving bees are trying to save their hive.

“The hive is pretty much doomed at this point,” Joe Lelinho, the beekeeper at Hilltop Honey, told CBS 2’s Vanessa Murdock.

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The colony came under attack by an exterminator with Western Pest Services.

“I guess he didn’t understand that these were honeybees,” Lelinho said.

“It was foolishness and ignorance,” David Rosen, the President of the Board of Trustees of the Cora Hartshorn Arboretum, added.

There’s a “no pesticide” policy at the Cora Hartshorn Arboretum, and the contract with the exterminator was simply to check mouse traps. But he took the liberty of spraying pesticide right into the entrance to the beehive.

It was a deadly mistake.

“Not only did all the foraging bees die,” Lelinho said, “but then the queen was affected by the spray inside the hive, and the queen died.”

3,500 bees were wiped out, and without a queen the colony can only survive a few weeks.

“Why would they spray the honeybees?” Judy Trigg, the Executive Director of the Cora Hartshorn Arboretum, pondered.

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“The bees are part of our program,” Rosen said. “They’re not a nuisance or a pest.”

On the contrary, the bees are here to educate — and to pollinate.

“This is a worker, this is a friend and a servant to mankind,” Lelinho said of the bees’ role.

The colony pollinates 8,700 acres around the arboretum, and that means a more fruitful harvest for things that people love to eat, like apples.

“Every third bite of food that we eat is there because of the honeybee,” Lelinho explained.

So revitalizing this colony is a must. But because of pesticide contamination, the entire hive — bees and all — must be replaced.

“We’ll be having a celebration when they return,” Trigg said.

And the celebration will likely be themed, “Honey, I’m home!”

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How must that exterminator feel right about now? Offer your thoughts and comments in the section below…