Extension Search / Diagnostic Labs / New Hampshire

University of New Hampshire Plant Diagnostic Lab

The Plant Diagnostic Lab at University of New Hampshire is New Hampshire’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 New Hampshire

Durham, New Hampshire

Disease diagnosis
DNA tests
Irrigation water
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.
DNA tests. PCR or sequencing to confirm a pathogen that can't be told apart by eye.
Irrigation water. Tests irrigation water for water molds such as Phytophthora and Pythium.
Photo diagnosis. Looks at photos you send first, and asks for a physical sample if the photos aren't enough.

The lab also screens for fungicide resistance.
Water testing covers Phytophthora capsici in ponds and irrigation water.
Some diseases can be identified from emailed photos.

Out of State

This lab doesn’t take samples from outside New Hampshire. 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 New Hampshire Extension office can often look at a sample free first.

Other Labs

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