Wilt Diseases

Wilt diseases are a serious threat to our urban landscape and forests. The wilt diseases (such as oak wilt, Dutch elm disease, and verticillium wilt) are vascular systemic diseases and should be sampled differently than other plant issues.

  1. Select branches that have a good transition from dying to living tissue. 

    • For help in selecting these transition areas, look at the leaves on the branches.  If leaves are beginning to wilt towards the end of the branch but the branch still has some healthy leaves present, select this type of limb.

  2. Select 5 or 6 branches that are about the diameter of your index finger (1/2 to 1 inch) and cut them to about 8-12 inches long.

  3. Place the pruned branches into a shipping box.

  4. Complete a General Form for the sample and place it in a separate plastic bag to protect it from any moisture.

  5. Seal the box and ship using next day delivery service.