A good sample is essential for an accurate diagnosis. Please follow these instructions carefully. The instructions on this page apply to sampling trees, shrubs, and vines from both commercial and home landscapes.
Related pages…
- Instructions for submitting arthropods (insects, mites, spiders, etc.)
- Sample submission forms: digital (preferred) | printable PDF for mailing
- Shipping instructions
- Instructions for samples sent from outside of North Carolina
To sample for disease diagnosis
- Select living plants with moderate symptoms.
- Collect samples when the foliage is dry and the ground is not saturated.
- Wilting and dieback are often the consequences of problems below ground. Dig a generous double handful of fine roots and one quart of soil from selected plants. Make sure you are collecting roots from the plant of interest, not from neighboring trees or shrubs.
- Place roots and soil together in a plastic bag and close securely.
- Place several branches that are showing different stages of decline in a separate, closed plastic bag. Do not add water or wet paper towels.
- Note: it is a common mistake to submit foliage/branches that are either entirely healthy or entirely dead. Usually these are not diagnostically informative. Instead, look for places where the dead bark/cambium/wood stops and the live tissue begins. If these are present, cut branches so as to include several inches on either side of the transition zone. Photos below show examples.
- For smaller plants, submit an entire plant, if possible. Cover the roots and soil with a plastic bag to prevent soil from getting on the foliage. Place the entire plant in another plastic bag and secure.
- If a tree or shrub is in such poor condition that it is to be removed, but yet it's too large to submit whole, the lower 8-12" of the main stem(s) and the top of the root system are very important diagnostically and should be included.
- Ripe fruits should be packed in absorbent material. They should not be bagged unless coming from outside of North Carolina, in which case double-bagging is required.
- Keep samples out of the sun, preferably refrigerated, until they can be shipped or taken to the clinic.
Look for and include transition zones between living and dead wood or cambium.
Cutting the branch in this way includes the diagnostically useful transition zone.
Don't forget the roots and soil!
In addition to the physical sample, a few photographs showing the symptoms of concern and their distribution in the landscape can be helpful to the diagnosticians. In the case of trees, be sure to include a picture of the whole crown and one or two from the base of the trunk. These can be uploaded to the database along with the sample information.
