DuPont’s Imprelis Herbicide Suspected of Killing Evergreens

A DuPont herbicide, Imprelis, marketed to professional landscapers this spring as an environmentally friendly product, is suspected of severely damaging or killing thousands of Norway Spruce and White Pine trees, some of which grow to be 80 or 100 feet.


imprelis herbicide norway spruce damage

Imprelis damage to Norway Spruce

Imprelis was intended for use as a post-emergent broadleaf weed killer to eradicate the likes of dandelion, clover, plantain, ground ivy, wild violets, and henbit. It was applied to golf courses, cemeteries, public parks, athletic fields, and lawns by landscaping companies nationwide.

imprelis herbicide damaged norway spruce

Imprelis Norway Spruce damage

Since mid-June, professional landscapers have reported thousands of complaints from customers whose Norway Spruce and White Pine trees are exhibiting wilted, necrotic, yellow needles; dead needles; wilted new shoots; desiccated and drooping candles; and twisted and distorted shoots. In most cases it appears that these stately evergreens reacted to Imprelis four to six weeks after the grounds near them were treated. In Columbus, Ohio alone, over two thousand evergreens have been damaged.

The Environmental Protection Agency announced Friday that they will begin an expedited review of Imprelis by the end of this month. Their ruling will determine if Imprelis is removed from the market or has its labeling revised.

Pete Landschoot, professor of turf-grass science at Pennsylvania State University, wrote in June, “In some cases, injury does not progress much further than slight curling and browning of new growth; however, in other cases complete dieback is observed. In severe cases, the entire tree turns brown and begins to lose its needles. It’s as if the trees were being poisoned through the roots, from herbicide spread deep by the soaking spring rains.”

imprelis herbicide white pine damage

Imprelis damage to a white pine

DuPont’s package label warns that grass clippings treated with Imprelis should not be used as mulch or put in compost piles, as Imprelis will survive the composting process and will still be active in the finished compost. Unsuspecting gardeners may damage their favorite flowers or vegetables, many of which are broad-leafed, just like the intended target plants.

So what are you to do if you suspect that one of your trees is suffering from Imprelis damage? DuPont has suggested that you surround the base of the tree with a soaker hose in an attempt to wash the chemicals through the soil. However, other scientists disagree with this suggestion, as Imprelis needs the activity of soil organisms to break it down, and waterlogging your soil will slow that action. In addition, DuPont warns that Imprelis has a high potential of polluting surface water via runoff for several months after application, so applying water to the poison and encouraging its movement may not be the responsible thing.

It’s ironic that Imprelis was marketed in a March press release as adding “to DuPont’s expanding portfolio of green industry products…with a reduced environmental impact.”

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About Todd Heft

Todd Heft is an organic gardener and freelance garden writer who lives in the Lehigh Valley, PA and has gardened for most of his life. When he isn't writing or reading about organic gardening, he's gardening. His first book, "Homegrown Tomatoes: The Step-By-Step Guide to Growing Delicious Organic Tomatoes In Your Garden" is available on Amazon now. Google
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6 Responses to DuPont’s Imprelis Herbicide Suspected of Killing Evergreens

  1. Judy Floor says:

    Was this product used by True Green? Did this product come in
    any other form.

    • Todd Heft says:

      Judy: You’d have to check with your local TruGreen franchise to see if they used it in their formulation – many landscape companies did. As far as I know, Imprelis was only manufactured in liquid form before it was banned.

  2. Gail Gardner says:

    DuPont’s advice would make this worse which only increases my suspicions of their motives behind this product. We need to spread this information as widely as possible.

    Do you have any data on how widely this product is being used? Many communities are now composting and giving away that compost to their residents to use on their lawns and gardens. There is no way to know whether what is in that compost has been treated with this or any other poison.

    • Todd says:

      I don’t have specific data on how widely it’s being used, but one article used the words “it flew off the shelf” in the fall and spring, so we can assume the use is very wide commercially.
      That’s a good point about the community composting. My suggestion temporarily would be to not accept yard waste unless you know its source and what if anything it’s been treated with. Gardeners using Imprelis-tainted compost might end up with a lot of sick or dying plants and God forbid if it’s unwittingly added to a vegetable garden.

  3. Brian says:

    If you have suffered damage to trees on your property after the spraying of Imprelis on your lawn or if you are a lawn care professional with customers that have been affected, we are interested in learning about your experience. Working together, we can make sure DuPont is held accountable for the damage their product has caused.

    Call us at 1-866-883-5350 to speak to an experienced attorney or visit us at

  4. Robin says:

    When are people going to realize that the herbicides and pesticides are just making things worse?

    I have noticed that within the past two years there have been at least 8 very large evergreen trees within a couple of blocks of our home that have completely died. I don’t know if it is a disease or the over use of all these chemicals.