Extension Search / Diagnostic Labs / Indiana

Purdue University Plant and Pest Diagnostic Laboratory

The Plant and Pest Diagnostic Laboratory at Purdue University is Indiana’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

Purdue University

West Lafayette, Indiana

Disease diagnosis
Insect ID
Plant ID
Virus tests
DNA tests
Turfgrass
Tree wilts
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.
Insect ID. Identifies insects, mites and spiders and whether they are a threat to the plant.
Plant ID. Identifies plants and weeds.
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.
Turfgrass. Diagnoses lawn and turf samples.
Tree wilts. Cultures or tests branch samples for wilt diseases such as Dutch elm disease, oak wilt or Verticillium wilt.
Photo diagnosis. Looks at photos you send first, and asks for a physical sample if the photos aren't enough.

Out-of-state samples cost more than samples from Indiana.
Photo-only questions go through the lab's digital submission tool.

Not Accepted

Soil or tissue testing
Pesticide residue testing
Water testing
Nematode soil counts
Mushroom ID for eating

Out of State

This lab takes samples from other states. Out-of-state fees are usually higher.

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 Indiana Extension office can often look at a sample free first.

Other Labs

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