Resources for Farm Advisors

Disease Diagnosis Support

We provide farm advisors with diagnosis support for warm season vegetables and field crops (including grains, vegetables, cotton, sunflower, and legumes). This service covers Kern, Tulare, Fresno, Kings, Merced, San Joaquin, Sacramento, Solano, Yolo, Colusa, Yuba, Sutter, Siskiyou, Modoc and Lake Counties. We are also currently covering vegetable crop diseases in the coastal counties.

To submit a sample, please fill out the specimen information form:

Printable version: 2019 PRINT SwettLab_Specimen Info Form

Fillable version: 2019 FILLABLE SwettLab_Specimen Info Form

Sample submission:

Drop off: Hutchison Hall rm 253. Fill out form and leave in the SAMPLE SUBMISSION fridge. Diagnosis forms are attached to the fridge. Please EMAIL Cassandra at to let me know you have submitted a sample. If I am around (rm 260) I am happy to go over the sample. Otherwise, bring in someone from the lab to go over it.

If no one is is rm 253, please leave samples with Maria Tuccori, rm 354 and EMAIL Cassandra at to let me know you have dropped it off. Diagnosis forms are on the door of 253, or you can email it to us separately.

Mail: Package samples in paper or plastic, well padded.  Include a specimen information form or email the fillable form to Cassandra at

Mail to:
Cassandra Swett
Department of Plant Pathology
University of California, Davis
1 Shields Ave
Davis, California, 95616