The NYTimes is reporting that several tree deaths are being linked to the use of the new herbicide Imprelis.
Imprelis uses pyrimidine carboxylic acid (trade name Aptexor )
A recently approved herbicide called
Imprelis, widely used by landscapers because it was thought to be environmentally friendly, has emerged as the leading suspect in the deaths of thousands of Norway spruce, eastern white pine and other trees on lawns and golf courses across the country.
Manufactured by DuPont and approved for sale last October by the federal Environmental Protection Agency, Imprelis is used for killing broadleaf weeds like dandelion and clover and is sold to lawn care professionals only. Reports of dying trees started surfacing around Memorial Day, prompting an inquiry by DuPont scientists.
There have been several reports from both outside and within the state of Michigan of herbicide injury on Norway spruce and white pine following application of the turfgrass herbicide Imprelis (a.i. aminocyclopyrachlor). Damaged trees have symptoms consistent with growth regulator type herbicides. Injury includes curling and twisting of new growth. Pictures and comments of damage observed in Indiana can be viewed at Purdue Extension’s Plant and Pest Diagnostic Laboratory website.
Read more at the Michigan State Extension Office
WSU has photos of the damage to conifers Wilting and browning leaves at the end of branches is the most obvious symptom.
DuPont is looking into this and recommends that you do not use Imprelis near spruces or white pines for now.