Extension Search / Diagnostic Labs / Wisconsin

University of Wisconsin–Madison Plant Disease Diagnostics Clinic

The Plant Disease Diagnostics Clinic at University of Wisconsin–Madison is Wisconsin’s university plant diagnostic lab. Send it a sick plant, an insect or a weed and it tells you what it is and what to do about it, usually for a small fee.

Lab Details

University of Wisconsin–Madison

Madison, Wisconsin

Disease diagnosis
Virus tests
DNA tests
Photo diagnosis

Open the lab's site for fees, forms and the mailing address.

Services

Disease diagnosis. Finds what is making a plant sick, from fungi and bacteria to cold, drought or chemical injury.
Virus tests. Serological tests such as ELISA that check a plant for specific viruses.
DNA tests. PCR or sequencing to confirm a pathogen that can't be told apart by eye.
Photo diagnosis. Looks at photos you send first, and asks for a physical sample if the photos aren't enough.

Out of State

This lab doesn’t take samples from outside Wisconsin. Use the lab in your own state.

Sample Tips

Call or email the lab before you send anything. What a lab accepts, and what it charges, changes.
Send a plant that is still sick, not one that has died. Include the edge where sick tissue meets healthy tissue.
Bag the roots and soil and tie the bag off at the stem, so soil stays off the leaves. Wrap leaves in dry paper and don’t add water.
Mail early in the week so the box doesn’t sit in a warehouse over the weekend.
Fill in the lab’s form completely: the plant, what you see, when it started and what has been sprayed or applied.

Not sure it’s worth a lab fee? The plant health key narrows a problem down from what you see, and your county Wisconsin Extension office can often look at a sample free first.

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