Extension Search / Diagnostic Labs / New York

Cornell University Plant Disease Diagnostic Clinic

The Plant Disease Diagnostic Clinic at Cornell University is New York’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

Cornell University

Ithaca, New York

Disease diagnosis
Plant ID
Mushroom ID
Nematodes
Virus tests
DNA tests
Turfgrass

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.
Plant ID. Identifies plants and weeds.
Mushroom ID. Identifies mushrooms. An ID is not a promise that a mushroom is safe to eat.
Nematodes. Extracts and counts plant-parasitic nematodes from soil or roots.
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.

Insects are identified at Cornell's separate Insect Diagnostic Laboratory.
Nematode tests include garlic bloat and pine wilt nematodes.
Packages from outside New York must be double-bagged.

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 New York Extension office can often look at a sample free first.

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