Collecting and Shipping Samples for the Diagnostic Lab
These guidelines should be followed for all types of plant samples.
- Fill out the accompanying Plant Diagnostic Checksheet as completely as possible
- Send a plentiful amount of FRESH plant material, it is best to include the entire plant when possible. Dig (do not pull) up the plant and ship as soon as possible.
- Send a sample characteristic of the problem that exhibits a range of symptoms.
- DO NOT ADD WATER OR WET PAPER TOWELS TO THE SAMPLE!
- Seal the plant material in a plastic bag and pack in a crush-proof container.
- Send only one type of sample in each bag.
- Send information in a separate plastic bag.
- Include necessary payment with sample.
- Send samples on or before Wednesday in order to avoid weekend storage at the post office
SPECIFIC COLLECTION GUIDELINES
(All samples should be sent in a plastic bag with a few air holes cut in it).
- Crops/Annual plants: Send entire plants, including roots and soil. Carefully dig the plants up. Send several plants showing a range of symptoms. Seal the roots in a plastic bag and place the entire sample in a larger plastic bag. DO NOT ADD WATER.
- Tree wilt diseases: Collect several branches ½ to 1 inch in diameter and about 12 inches long. The samples should be in the process of wilting but not dead.
- Trees/shrubs (foliage diseases, cankers, and fruit rots): Collect several branches 10-12 inches long (or fruit) showing a range of symptoms.
- Turf: Samples should be 6 inches square by 4 inches deep. Collect the sample near the margin of the affected area so that a range of diseased and healthy tissue is included.
NEMATODE COLLECTION GUIDELINES
- Diagnostic sampling for initial detection of a nematode problem: Separate samples from healthy and affected areas are essential for a reliable diagnosis of nematode damage. Collect several soil and root cores to a depth of 6 to 8 inches from the margin of the affected area. The soil cores should be bulked, mixed, and subsampled. Repeat the sampling process nearby in the healthy area. Submit 1 pint of soil and roots. Include the plants if possible.
- Advisory sampling for management purposes (for soybean cyst):
Collect samples prior to planting. Divide the field into sections based on soil type and cropping history. From each section collect at least five soil cores taken at a depth of 6 to 8 inches. The soil cores should be bulked, mixed, and subsampled. Submit 1 pint of soil.
- Sampling for pine wilt:
Collect a branch at least 2 inches in diameter and 6 to 8 inches long from adjacent to the trunk of the tree. Place sample in plastic bag immediately after collection and keep cool until shipping. Do not add water to the sample. Mail early in the week (Monday – Wednesday). Allow 1-2 weeks for a reply.
There will be a $5.00 diagnostic surcharge per plant or cost of individual test fee ($10 to $20).
Samples not submitted through the County extension office will have a additional overhead surcharge.
Distance diagnostics – no charge.