Vascular Wilt Samples (Dutch Elm Disease, Oak Wilt, Verticillium Wilt)
Collect 3 small branch pieces, 1/2 inch in diameter, 4 to 6 inches long, from recently wilted branches. Pieces from the living sections of branches that are partially alive and partially dead are best. * DO NOT * send branches that have dried out and have a brown layer directly under the bark.
Collect soil samples from several locations in a field to be tested for nematodes, pea/bean root rot pathogens or other soil-borne pathogens. Try to collect a sample that represents the soil from all areas of the field. These small samples (subsamples) can be mixed together for shipment.
For nematode and Verticillium testing submit 1-2 cups of soil.
For Aphanomyces race-specific testing, submit 2-3 gallons of soil per sample. For detailed instructions on how to collect this sort of sample, as well as a submission form, see “How to Submit a Soil Sample for Aphanomyces Race Testing on Alfalfa“.
For pea root rot testing, submit 1-2 gallons of soil per sample. For detailed instructions on how to collect this sort of sample, see “How to Submit a Soil Sample for Pea/Bean Root Rot Testing“.
Cut plugs that are 3 to 4 inches in diameter from the edge of the affected area where healthy turf meets diseased turf.
Bacterial Ring Rot and Dickeya Samples
Call the PDDC when planning to submit a sample for bacterial ring rot testing to verify there will be a clinician available to perform the test in a timely manner and to get details on the type of sample to submit.
Suspected Soybean Rust Samples
Select a representative group of leaves (or other plant parts) that exhibit the range of symptoms that you have observed in the field.
Be sure to collect detailed information on the location where the sample was collected so that the site can be revisited if necessary. If you know the GPS coordinates of the site, please provide these.
If possible, place the leaves between layers of cardboard and paper towels to keep them flat (i.e., layer the materials as follows – cardboard, paper towel, leaves, paper towel, cardboard, paper towel, leaves, paper towel, cardboard, etc.).
Place the leaves in a self-sealing plastic bag and seal the bag shut.
Place this bag inside a second self-sealing plastic bag, being particularly careful that the outside of this second bag does not become contaminated.
Keep the leaves cool (e.g., by placing them in a cooler or refrigerator) between the time of collection and the time when they are shipped to the PDDC.
Ship the samples to the PDDC by overnight mail whenever possible.