You may submit digital samples, physical plant samples or a combination of both to the Plant Disease Clinic. Both plant and digital samples should be submitted to the Plant Disease Clinic through your local Virginia Cooperative Extension (VCE) office. There is a $35 fee (effective 10/1/21) for submitting a sample (digital and/or physical) to the Plant Disease Clinic. A sample should represent a single problem. If your local VCE agent can diagnose the problem at the county level, no charge will be incurred. Your local VCE office can provide instructions on how to pay the fee.
The charge for in-state samples for sample diagnosis (whether digital, physical or a combination) is $35.00, which must be pre-paid before submitting a sample to the Plant Disease Clinic. Payment must be made by one of these two options: 1) credit card through your local VCE office’s Destiny One payment website OR 2) by cash or check at your local VCE office. Note: The Plant Disease Clinic does not accept cash or check payment. Your local VCE office can provide details on paying via the VCE office’s Destiny One payment website.
For plant disease diagnosis or identification of non-weedy plant samples the Plant Disease Diagnostic Form (Pub #450-097) must be completed and included with the sample; your local VCE office can provide the form to you. It can be electronically filled OR printed and completed as a hardcopy. Refer to more details in the “Completing the Plant Disease Diagnostic Form” section below.
- Contact your local VCE office and work with your local VCE agent or staff member who can assist you with the submission process. Your local VCE agent may be able to diagnose the problem without having to submit a sample to the Plant Disease Clinic and, in that case, there would be no charge.
- Complete the Plant Disease Diagnostic Form (Pub. #450-097) accurately and completely—include it with the physical or digital sample. This form is available at your local VCE office.
- Options for submitting a digital sample, a physical sample or a combination (digital + physical sample):
- Digital sample: Review the Guidance on Submitting a Good Digital Sample and submit images to your local VCE agent/staff who will upload them to the Plant Disease Clinic’s database for review.
- Physical sample: Carefully review the “Collecting a Plant Sample for Diagnosis” and “Packaging a Plant Sample for Shipment”. Your local VCE office can help you navigate this process as well.
- Both a digital + a physical sample: Follow instructions in 3a and 3b (above).
- Pay the $35 diagnostic fee. (Note that the $35 fee is for a single plant problem.) Payment must be made via your VCE office’s Destiny One payment website OR by check or cash at the VCE office. (Note: The Plant Disease Clinic does not accept check or cash payments.) The fee must be paid prior to shipping a physical sample (include the payment receipt in the package). If submitting a digital sample alone, or in conjunction with a physical sample, submit the payment receipt electronically to your local VCE office agent/staff.
- Review “The Plant Disease Diagnostic Report” (below) for information on the diagnostic reporting process.
- The in-state charge for diagnosis of symptoms on one plant sample (whether digital or physical or a combination) is $35.00, which must be pre-paid before submitting a sample to the Plant Disease Clinic. The $35 fee does not cover multiple plant problems, but is for a single plant problem.
- Payment by credit card must be made by the client through their local VCE office’s Destiny One payment website OR by check or cash at your local VCE office. VCE county staff can provide guidance on making a credit card payment via Destiny One. The Plant Disease Clinic does not accept cash or check payments.
- No refunds will be given for samples submitted to the VT Plant Disease Clinic, regardless of whether a specific diagnosis was possible for the sample.
- Samples that are deemed “insufficient for diagnosis” can be resubmitted (only the same problem may be resubmitted) at no extra charge. Simply include the digital or printed report with the follow-up sample.
- A physical sample that is submitted as a follow-up to a digital sample will not be assessed an additional fee.
The information provided on the Plant Disease Diagnostic Form [Pub. #450-097] is very important to help ensure accurate diagnosis of samples. Incomplete and/or inaccurate information on the form may reduce the likelihood of the best and most accurate diagnosis and/or result in an inappropriate control recommendation. Background information provided on the form is especially critical for diagnosticians who are working in a laboratory and cannot observe the plant in the field/landscape/nursery location. Also, in cases in which no pathogen is found on the sample submitted, the information provided on the form is essential for troubleshooting the problem. Therefore, please take time to complete both pages of the form as accurately and completely as possible. Your local VCE office can provide the Plant Disease Diagnostic Form to you and step-by-step instructions for completing the form are available.
We encourage submission of a digital sample even when a physical sample is being mailed. A digital sample provides important background information that is very helpful for the diagnostic process. If the problem can be accurately diagnosed from images, you will receive a quicker answer without having to send a sample, so it may be beneficial to first submit a digital sample. If a physical sample is subsequently requested, there is no additional charge, and details on the type of physical sample needed will be provided to you.
- Digital samples should be submitted through your local county Extension office. Email (or provide by other means) the images to your local county Extension agent, along with a completed Plant Disease Diagnostic form (#450-097), which can be obtained from your local VCE office.
- Please review the VT Plant Disease Clinic’s Guidelines for Submitting a Good Digital Sample to the Plant Disease Clinic before submitting digital samples.
- If the problem can be diagnosed by your local VCE agent, there will be no charge for diagnosis.
- If the sample needs to be submitted to the Plant Disease Clinic, the client will need to prepay the fee and provide a receipt for payment to the local VCE office staff or agent.
- Once payment has been made, the VCE Extension agent or staff will submit the digital sample, the diagnostic form and payment receipt to the Plant Disease Clinic’s database for review.
- If, upon review of the digital sample, the diagnostician determines that other information/item(s) are needed (e.g. better images, a physical sample, additional information) a request for such item(s) will be sent to the client (if an email has been provided) AND the relevant VCE agent/staff. No additional charge will be incurred by the client for submitting the requested items.)
- The process for submitting physical samples is similar to the process for submitting digital samples; however, the client has the option of packaging and sending the sample directly to the lab once payment has been made on their local VCE office’s Destiny One payment website. However, it is recommend that you work with your local VCE office when submitting any sample. It may be possible to diagnose the problem at the county level, in which case there will be no fee, OR office staff can assist you to ensure the best sample for accurate diagnosis is submitted.
- If you work with the local VCE office, the office may package and ship your sample to the lab.
- Whether you send the sample yourself or submit it through the local VCE office, you will need to prepay for the sample(s) by credit card via your local VCE office’s Destiny One payment website OR by check or cash at your local VCE office. (Note: The Plant Disease Clinic does not accept cash or check payments.) Guidance on paying the fee can be provided by your local VCE office.
- Remember to mail physical samples early in the week to avoid delays in the mail and to include a completed diagnostic form and payment receipt in the package.
The accurate diagnosis of plant disease is highly dependent upon receiving a sample that is both appropriate for diagnosis and in good shape. Wet foliage should be blotted dry with a paper towel before packaging to avoid secondary rot during shipment. A dry paper towel may be included with the foliage to absorb excess moisture.
Packaging the sample appropriately and shipping early in the week ensure receipt of a sample in the best condition possible. When a sample is received that is severely wilted, dried, crushed, broken, covered in soil, rotting and/or in advanced stages of decay, accurate diagnosis is usually impossible. Avoid exposure to high temperatures after sample collection and, if not shipping immediately, store in a refrigerator, if possible. (Refer to the Guidance on Submitting a Good Physical Sample for Plant Diagnosis [coming soon!] for more details on submitting different types of plant samples.)
Your local VCE Extension office can assist you with submitting the best sample for accurate diagnosis and, if you submit a digital sample prior to submitting a physical sample, a Plant Clinic diagnostician can provide details on the type of physical sample needed. (There is no additional charge for submitting the follow-up physical sample.)
- The best sample for accurate diagnosis is collected from a plant in an early stage of symptom development or decline.
- When practical, submission of a whole plant, including the root ball, is highly desirable. Dig plants; do not pull them out of the ground. Shake loose soil off gently, leaving at least a pint around the root ball. Root balls with soil should be placed in a plastic bag that is tied off at the base of the plant to keep foliage clean. Then place the whole plant in another plastic bag.
- If the problem could be on the lower stem or roots of a large plant, such as a tomato or hemp plant, cut the stem about 12” above the soil line. Dig the root ball and gently shake off excess soil, leaving at least a pint of soil on the root ball. Place the root ball in a plastic bag and tie off at the base of the stem. Place the stem and root ball in another plastic bag. Collect symptomatic stems with leaves and place in a separate plastic bag.
- For some smaller plants (e.g. bedding plants, soybeans) it is advisable to send several plants since roots and/or stem tissue may need to be cultured on multiple types of culture media and adequate root/stem tissue will be needed. Dig plants and gently shake off loose media/soil, keeping at least a pint of media/soil with the roots. Keep foliage dry by wrapping the roots/soil in cling wrap. Place the whole plants in another plastic bag.
- For small seedlings, shipping a dozen or more plants is advisable. Keep foliage dry by wrapping the roots in soil/media in cling wrap. Place the whole plants in another plastic bag.
- For large shrubs or trees, roots can be collected separately. Dig a large handful of the fibrous roots and place in a plastic bag with at least a pint of soil from the root zone. Collect symptomatic foliage/branch samples (with leaves still attached to stems to keep leaves fresh) and package in a separate plastic bag.
- Many tree problems are difficult for a remote diagnostic laboratory to diagnose, since the whole tree cannot be examined. Many trees slowly succumb to wood decay organisms or suffer from multiple injuries (both abiotic and biotic in nature) over many years that lead to a gradual decline. Laboratory diagnosis of these types of tree problems is often not possible, and trees with these types of problems are not likely to recover. Consulting a local certified arborist may be more appropriate in such situations. Branch cankers, leaf spots/blights, fungal root rot diseases and bacterial leaf scorch are examples of some problems that we are generally able to diagnose. It is advisable to discuss submission of a particular tree problem with your local VCE agent/staff before submitting a sample to the Plant Disease Clinic.
Packaging a Plant Sample for Shipment
- Plant samples should be sealed in a plastic bag with soil contained in a separate plastic bag (a root ball can be placed in a plastic bag that is tied off at the base of the stem) to avoid soiling/damaging foliage.
- Tissue that is wet will rot during shipment, so blot dry any foliage that is wet and include a dry paper towel to absorb excess moisture.
- The completed Plant Disease Diagnostic Form (#450-097) should be protected from moisture or damage in the package (e.g. enclose in a plastic bag).
- Include the payment receipt if it was not digitally submitted by your local VCE agent/office and protect it from moisture or damage in the package.
- Samples should be packaged appropriately to prevent damage in transit and ensure plant tissue is in the best shape possible when received by the laboratory.
Shipping Plant Samples
Ship plant samples early in the week so the sample does not deteriorate in the mail over the weekend. If samples are received late in the week or before a holiday weekend, store them in a refrigerator for shipment early the following week.
The Diagnostic Report
The plant disease diagnostic report will be sent electronically to your local VCE office and the agent/staff member who assisted you. A copy will ALSO be sent to you if a legible and correct email address was included under the grower information on the Plant Disease Diagnostic form. The report will include a recommendation.
- A range of lab techniques are used to identify fungi, bacteria and other plant pathogens. Some pathogens can be identified relatively quickly (e.g. by microscopic examination), while others may require a longer process for identification (e.g. diagnosis by molecular techniques, culturing, carbon utilization analysis, etc.). Diagnosing abiotic (non-living) problems often takes longer than identifying a biotic problem, since there may be a longer process of elimination.
- Diagnosticians also frequently consult with other specialists who may have specialized expertise on a particular problem and/or crop/plant type and that can also add time to the diagnostic process.
- Therefore, a client may receive a diagnostic report within a few days to two weeks of sample submission. If you do not receive a report within two weeks, please contact your local VCE office or agent/staff member who can check with the Plant Disease Clinic on the status of the sample.