Extension Search / Diagnostic Labs / Oregon

Oregon State University Plant Clinic

The Plant Clinic at Oregon State University is Oregon’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

Oregon State University

Corvallis, Oregon

Disease diagnosis
Insect ID
Plant ID

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.

The OSU Insect ID Clinic, housed with the Plant Clinic, identifies insects and spiders.
Home gardeners are asked to start with their county Extension office, which consults free.

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

Other Labs

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