How to Submit a Sample
For additional information on how to collect and submit a sample for diagnosis contact your local University Extension Office, or call the Plant Clinic at (217) 333-0519.
Suggestions for Specimen Collection and Submission
- Collect fresh specimens. Send a generous amount of material, if available.
- Ship in a crush-proof container immediately after collecting. If holdover periods are encountered, keep specimen cool. Mail packages to arrive on weekdays.
- Avoid weekend layovers.
- Include completed Plant Clinic Specimen data form and fee with each sample submitted.
- Note: Diagnoses and recommended controls by the University of Illinois Plant Clinic are based solely on the material and information submitted. The less representative the sample, and the less complete the information provided, the greater the chance for misdiagnosis.
Submitting Plant Specimens for Disease / Injury Diagnosis

- Leaf - Collect early and late stages of infection. Press leaves between heavy paper or cardboard.
- Fleshy Plant Parts - Samples with a rot disease should not be sent in an advanced stage of decay. Collect fresh specimens with early symptom development. Wrap in newspaper.
- Canker - Select recently produced cankers. Submit the whole cankered portion where possible; preferably with healthy wood above and below the canker.
- Wilt or General Decline - Send the entire plant, with roots, if feasible: submit several plants, from healthy to severely infected. Dig, do not pull plants from the soil so diseased roots will remain intact. If the whole plant cannot be sent, select samples from areas of active symptom development. Include the intact root system if root rot is suspected. Include photos.
- Turf - Submit several 4-inch plugs of grass cut as deeply as roots will hold soil. Plugs should show gradation from healthy to severely diseased. Do not wrap leaves or fleshy material in plastic - use newspaper.
- Complete and include one of the following forms with the sample:
- Field Crop Form
- Form to use with all other samples
Submitting Nematode Specimens
- Diseases caused by nematodes require special attention. See Report on Plant Disease No. 1100 for detailed instructions on the handling and shipping of nematode infested material.
- Complete and include the Nematode Soil Sample Form with the sample.
Submitting Insect Specimens
- Care should be taken to package insects so they arrive unbroken. Be sure to separate and label the insects if two or more are included in the same package and provide appropriate information on each.
- Adult specimens such as flies, grasshoppers, cockroaches, wasps, butterflies and beetles can be submitted in a dry, crush-proof container. Do not tape insects to paper or place them loose in envelopes.
- Larvae or soft-bodied specimens such as aphids, caterpillars and grubs should be submitted in a small leak-proof bottle or vial of 70 percent alcohol. Rubbing (isopropyl) alcohol is suitable and readily available.
- Complete Form to use with all other samples and include with your insect sample.