imprelis ® damage to trees primer

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Imprelis® Damage to Trees Primer

University of Minnesota Extension

Minnesota Department of Agriculture

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What is Imprelis® What Does it Do?

A Broad-leaved Herbicide for Turf Use Introduced by DuPont in Spring, 2011 Active Ingredient: aminocyclopyrachlor

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What is Imprelis® What Does it Do?

“Control Weeds Even on Rainy Days

DuPont Imprelis herbicide...control dandelion, clover and plantains, as well as tough broadleaf weeds...even during reseeding or rainy days...a low application rate... and is the first compound in an advanced generation of herbicides.

Turf Magazine - November, 2010TURF SCIENCENew Products

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What is Imprelis® What Does it Do?

Turf Magazine - November, 2010TURF SCIENCENew Products

“Imprelis® is readily absorbed by plant leaves and roots, stopping the growth of target weeds by interfering with the hormonal balance necessary for normal shoot and root development.”

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What is Imprelis® What Does it Do?

Aminocyclopyrachlor & Clopylralid Clopyralid introduced...as a broadleaf

herbicide...

Clopyralid found in organics waste stream ...

Decomposition processes in compost...did not degrade the molecule.

Compost was herbicidal.

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What is Imprelis® What Does it Do?

Similar to Clopyralid:

Long residual Not biodegradable High concentrations remained in plants Herbicidal impacts at very low concentrations Recycled in grass clippings/Tree leaves

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What Did DuPont Do?

By June, 2011, damage to trees and shrubs was reported...

By end of summer, Imprelis® was pulled from use

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Symptoms of Imprelis® Damage

Evergreen and deciduous... Dead buds, shoots, pine candles... Twisted, fused needles... Contorted, chlorotic leaves... Tumorous growths on twigs, stems... Twisted, “stretched” twig growth... Death

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Symptoms of Imprelis® Damage

Colorado Spruce

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Symptoms of Imprelis® Damage

Colorado Spruce

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Symptoms of Imprelis® Damage

Black Hills Spruce

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Symptoms of Imprelis® Damage

Norway Spruce

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Symptoms of Imprelis® Damage

White Pine: 2011 on the left, 2012 on the right

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Symptoms of Imprelis® Damage

White Pine

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Symptoms of Imprelis® Damage

Northern White Cedar

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Symptoms of Imprelis® Damage

Honeylocust

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Symptoms of Imprelis® Damage

Honeylocust

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Symptoms of Imprelis® Damage

Ginkgo

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Symptoms of Imprelis® Damage

Freeman Maple

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Symptoms of Imprelis® Damage

Cottonwood

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Susceptible Plants?

To Date: all woody trees, shrubs, vines

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Treatments? Avoidance?

Damage is to new growth

Prune and remove damaged growth

Chemical moves with water...water moves down-hill

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Treatments? Avoidance?

Remove all contaminated materials Capture and remove grass clippings, leaves,

wood and any other plant debris that might be contaminated through at least 2014

Replace contaminated soil As much as you can around the new planting site Amend existing soil remaining around the edges

with activated carbon

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Compensation for Tree Loss?

Carefully document all damage: Maintenance records Dates Photos Symtomology

DuPont claim site: www.imprelis-facts.com

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For More Information

Imprelis® Update: 2012 Field Notes on Injury and Recovery. www.ppdl.purdue.edu.

A Turf Professional’s Guide to Suspected Imprelis® Herbicide Injury in the Landscape. www.ppdl.purdue.edu/PPDL/pubs/briefs/ImprelisLCO.pdf

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Acknowledgement

All Imprelis® symptoms images were generously shared by:

Manuel Jordan: Heritage Shade Tree Consultantsand

John Lloyd: Plant Health Doctors.com