Plant Diagnostic Lab

How to Submit a Sample

Please include a completed lab form (in pdf format or as a MSWord 2003 document) with your sample. If you don't have Acrobat Reader, you can download it for free:

NDSU Extension personnel: if you are a registered PDIS Submitter, please use PDIS to submit sample information. Click PDIS Login in horizontal menu bar.

Below are some tips on how to collect and ship good quality samples.

Plants: For general plant problems, try to send several affected plants showing a range of symptoms. Dead plants rarely are informative - avoid sending completely dead plants. Try to send entire plants, when feasible, since some above-ground symptoms can be attributed to a problem with the lower stem or roots. When digging plants, try to keep the roots intact with the soil, as a root ball, to help prevent the sample from drying out. The root ball should be wrapped in damp (not wet) paper towels, and wrapped in a separate plastic bag (tied off at the stem) to prevent soil from coming in contact with leaves. The foliage should be wrapped in dry paper towels to absorb moisture (to prevent decay), and the entire sample should be placed in another, loosely folded plastic bag. Do not allow leaves, paper tags, or labels to come in contact with soil. If possible, place a few leaves flat in a separate envelope.

Mushrooms and fruits: Wrap mushrooms or fruits in dry paper towels or newspaper and place in sturdy box to avoid crushing.

Insects: Send small insects in vial of alcohol (never in an envelope). Pack large insects, such as moths, in cotton. Please DO NOT SEND LIVE INSECTS. Insects should be dead.

Turfgrass samples: Plugs that are about 3-5" in diameter and deep enough to include the roots (usually about 3") are ideal. The best sample consists of a completely diseased plug, a healthy plug, and a plug from the transition zone between diseased and healthy turf.

Dutch elm disease testing and other vascular wilt testing: Live, symptomatic branches that are at least 1" in diameter and 6-8" long should be submitted, with leaves attached.

Soil samples for nematode extraction or root rot indexing: 1. Use a soil probe to collect samples, 6-8 inches in depth. 2. Using a zigzag pattern, collect 10-20 soil cores per every 10 to 20 acres. 3. Collect cores from areas of similar soil type and crop history. 4. Dump cores from each 10-20 acre set into a bucket or tub and mix thoroughly. 5. For nematode screening, send 1 pint (2 cups) of mixed soil in a soil sampling bag or plastic zippered bag. For Aphanomyces indexing, send about 1 gallon (32 cups) of soil per 10-20 acre set. Label the bags with a permanent marker. Don't allow paper labels to come in contact with soil. 6. Store sample in a cool, dark place until shipped to the lab. Ship as soon as possible.

Physical location

Waldron Hall, room 206. Click here for a campus map (pdf format).

Mailing Address

NDSU Plant Diagnostic Lab
Department of Plant Pathology
306 Walster Hall
PO Box 5012
Fargo, ND 58105-5012