Millions of dollars worth of spruce and pine trees across the country have mysteriously withered and died in the past few months. The likely culprit is an herbicide marketed as a way to control lawn pests like dandelions.

The herbicide is Imprelis, a new product from DuPont. It was supposed to be better for the environment than its predecessors and has been sold at a premium to professional landscapers. DuPont claims it "may not have been mixed properly or was applied with other herbicides." Landscapers just want to know if they're going to have to pay to replace the trees that died on their watch.

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DuPont may have developed the new pesticide in order to circumvent bans on herbicides that kept grass clippings from decomposing properly, making them verboten to commercial composters. The company is probably crossing its fingers that it'll get the OK to compost Imprelis-soaked materials: those dead trees mean there's a lot more material ready to compost.

Oh, and DuPont's also moving towards offering this stuff as a consumer product. But if you like your trees (or your dandelions! Why is everyone always so against dandelions?), you'll either steer clear or follow these instructions from DuPont: "When applying Imprelis, be careful that no spray treatment, drift or runoff occurs that could make contact with trees, shrubs and other desirable plants, and stay well away from exposed roots and the rootzone of trees and shrubs.” So basically, when you’re trying to spray plant-killer on plants, try not to get it on any plants.

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