In the corporate world's tortured language, workers are no longer fired. They just experience an “employment adjustment.” But the most twisted euphemism I've heard in a long time comes from DuPont: “We are investigating the reports of these unfavorable tree symptoms,” the pesticide maker recently stated.

How unfavorable? Finito, flat-lined, the tree is dead. Not just one tree, but hundreds of thousands all across the country are suffering the final “symptom.”

The culprit turns out to be Imprelis, a DuPont weed-killer widely applied to lawns, golf courses, and — ironically — cemeteries.

Rather than just poisoning dandelions and other weeds, the herbicide also seems to be causing spruces, pines, willows, poplars, and other unintended victims to croak.

“It's been devastating,” says a Michigan landscaper who applied Imprelis to about a thousand properties this spring and has already had more than a third of them suffer outbreaks of tree deaths. “It looks like someone took a flamethrower to them,” he says.

At first, DuPont tried to dodge responsibility, claiming that landscape workers might be applying the herbicide improperly. The corporation even urged customers to be patient and leave the tree corpses on their lawns to see if they'd come back to life in a few years.

However, faith-based landscaping was a hard sell. Disgruntled homeowners began filing lawsuits. Then DuPont had its own “aha!” moment when trees on the grounds of the DuPont Country Club also developed the “unfavorable symptoms” of Imprelis poisoning.

So, with DuPont's cooperation, the EPA has finally banned sales of the tree-killing herbicide. But because of inadequate testing and a rush to profit, the poison will remain in the soil — and our water— for many moons. Trees will continue to die. Will we never learn?