Extension Search / Diagnostic Labs / Illinois
University of Illinois Plant Clinic
The Plant Clinic at University of Illinois is Illinois’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 Illinois
Urbana, Illinois
- Disease diagnosis
- Insect ID
- Plant ID
- Nematodes
- Virus tests
- DNA tests
- Turfgrass
- Tree wilts
- Hemp
- Herbicide issues
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.
- 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.
- Tree wilts. Cultures or tests branch samples for wilt diseases such as Dutch elm disease, oak wilt or Verticillium wilt.
- Hemp. Takes industrial hemp samples. Most labs ask for your state hemp license number, and none take marijuana.
- Herbicide issues. Looks at herbicide injury or tests weeds for herbicide resistance.
- DNA tests include herbicide resistance testing in weeds such as Palmer amaranth.
- Hemp samples have been free for growers in Illinois, Indiana, Michigan and Wisconsin under a USDA project.
- Packages from outside Illinois must be double-bagged with every seam sealed.
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 Illinois Extension office can often look at a sample free first.
Other Labs
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