It's challenging to write directions for every possible scenario. If you feel uncertain about how to collect a good sample of what the cost might be for your case, please contact the lab at (612) 625-1275 or email [email protected] with questions.
Collect symptomatic plants that are still alive. Collecting plants in various stages of decline is a good strategy for collecting a sample. If shipping, it's usually better to mail plant material in a box rather than an envelope.
For herbaceous plants, if possible, send entire plant(s). Include as much of the root system as possible. To preserve root integrity, dig (rather than pull) symptomatic plants from the ground. Wrap roots in plastic (left photo). Wrap the plant(s) in dry newspaper and place in plastic (right photo). Prices vary (usually $50- $65). Call or email if you have questions.
Spruce and Fir
For spruce and fir, look for bud-scars (see arrows in photos) to help ensure that at least 3 year's growth (see yellow brackets in the left photo) is included in the sample. Some diseases are not present on the newest growth, so it's important to include older growth. Wrap in dry newspaper and then in plastic for shipping. Most problems of spruce and other conifers can be diagnosed with routine tests, so the fee is $50.
For oak disease analysis ($65- $85), collect your sample from actively wilting branches. If possible, include 3-5 branches (not more). Branches with about 1-inch diameter are a nice size for testing, but it is more important that the branches are from actively wilting areas on the tree. Enclose in a plastic bag to retain moisture. Keep cool until submitted. When there is risk of oak wilt, seal the wounds on the tree right away using one coat of shellac or water-based paint. Unless the sample is a trunk cookie, please keep branch diameter under 4-inches and length less than 4-feet.
Verticillium Wilt or Dutch Elm Disease testing
For Verticillium Wilt or Dutch Elm Disease testing (wood culture $65), collect your sample from actively wilting branches. If possible, include at least 5 branches. Branches with about a 1/2-inch to 1-inch diameter are a nice size for testing, but it is more important that the branches are from actively wilting areas on the tree. Wrap sample in plastic to retain moisture. Keep cool until submitted.
Virus Testing: Some tests are unavailable - call before sending
For virus testing, collect symptomatic leaves, stems, or entire plants. Wrap in aluminum foil. It is very important that these samples do not dry out during shipment. Do not add extra water to the bags. Prices vary from $50- $100+. As of September 2021, some tests (TEM / ISEM) are currently unavailable. Call or email if you have questions.
Nematode analysis requires that nematodes remain alive. Therefore, it is important that soil for nematode testing is not exposed to high temperature and/or desiccation.
- Garlic Bloat Nematode Testing: If you are applying to be a vendor at the Garlic festival, follow the Vendor Application directions for collecting and submitting samples. Growers who are not applying to the Garlic Festival, can follow the same directions, but there is no deadline. You can send samples anytime.
- Soybean Cyst and Corn Nematode Testing: The University of Minnesota Southern Outreach Center does these tests.
- Other nematode tests: For soil samples, ship them in sturdy plastic bags to retain moisture. More guidelines for sample collection are available upon request. Please refer to the above link for instructions.
Submit a Sample Submission Form
Download PDF Sample Submission Form
Pre-payment by check is preferred for non-commercial clients. Make checks payable to the University of Minnesota and include with your sample. (Please check our current prices.) If payment is not included with the sample, an invoice will be sent by the University of Minnesota Central Accounting Department. Commercial clients may prepay; however, most chose to be set-up in the University of Minnesota Central Accounting system.
Mail or hand deliver samples shortly after collection. Mail samples early in the week to avoid weekend layover.
Plant Disease Clinic
Department of Plant Pathology
495 Borlaug Hall
1991 Upper Buford Circle
St. Paul, MN 55108
Hand Delivery address:
(Lab hours: Tuesday – Friday 8:30am-4:30pm)
1519 Gortner Ave
105 Stakman Hall
St. Paul, MN 55108
Campus Map and information for Stakman Hall
St. Paul Campus Map (pdf)
Interactive Campus Map
Out of State Clients
Samples that are collected from outside Minnesota must be double bag and sealed (ex. two zip-lock freezer bags). Place the sealed bags in a sturdy shipping container. Our lab has USDA APHIS permits to accept samples from the continental U.S.