- Collect samples from branches that are showing symptoms but are not dead.
- For Dutch elm disease, oak wilt, and Verticillium wilt testing, branch specimens should consist of four to six pieces, measuring 6 to 8 inches long, and 1/2 to 1 inch think.
- When submitting cankers, include the portion of the branch at the border between discolored and healthy bark.
- Send to:
327 Bessey Hall
Iowa State University
Ames, IA 50011
(515) 294-0581