Agronomic Crops

Samples accepted in person and digitally
All samples require appropriate request form

A full and complete history of the specimens, surrounding plants, and symptoms are needed. 


Sampling Instructions:

  • Carefully examine your plants to accurately assess symptoms and distribution. Complete the Plant Diagnostic Request Form in entirety, and include it with the sample in a separate zip-seal bag.
  • Collect a representative symptomatic sample that fully describes the observed problem. The entire plant may be needed for the most accurate diagnosis. This is especially important with vascular and root rot pathogens. It is important to look at roots and lower stem to have whole picture of the problem. Digging out the plant helps to preserve the integrity of the root system.
  • Submit a generous amount of plant material. If the plants are small (i.e. seedlings), send several plants. Samples from different plant species should be bagged separately and labeled.
  • A mixture of living tissue and necrotic tissue is needed to isolate the pathogen and diagnose the disease. Do not send dried or dead plants
    • Leaf or Stem Samples: place the sample in a zip-seal bag as soon as it is collected. Do not use paper bags.
    • Vegetable Samples: Separate vegetable samples from roots and top growth material. Vegetables with tender skin should be placed in a paper bag as soon as it is collected. Vegetable with a tough skin (grapes, apples, plums, etc.) can be placed in zip-seal bags.
    • Entire Plant Samples: For entire plant samples, bag (plastic) the roots and seal at the soil line with a twist tie or a rubberband. Do not cut the root ball off the above-ground plant parts. Cover the top plant growth with a second plastic bag.
  • Place the sample/samples in a crush-proof box and mail it using next-day or two-day shipping option or deliver the sample in-person to minimize damage from cold or heat and allow the sample to arrive fresh. 
  • Write “Live plant Sample” on the outside of the box
  • Photos of the problem in the field are always helpful, and may be emailed to

Samples submitted digitally: 
Send completed submission form and include as an attachment with relevant digital images in an email message to
Click for more Digital Sample submission details. 

Samples mailed:
C. Wayne Ellett Plant and Pest Plant Diagnostic Clinic 
Ohio State CFAES Wooster Campus
c/o Dr. Francesca Rotondo
234 Selby Hall, 1680 Madison Ave., Wooster, OH 44691

Samples hand-delivered:
Requires coordination with Dr. Rotondo: (330-263-3721) |