Wetwood

Pathogen Type
Scientific Name
Many genus and species involved
Frequency
3
Severity
2
Hosts

The disease affects a wide range of trees, but is most commonly encountered on elm.

Symptoms
The disease causes an internal pressure which, in turn, causes a waterish material called slime flux to ooze out through wounds in the bark. Slime flux is caustic (very alkaline). Generally, the bark is slowly bleached of its coloring where the slime flux runs down the outer bark. Often there is an unpleasant odor associated with the slime flux for a short period during the growing season.
Cycle

There is a complex of bacteria which cause wetwood and little is known about infection and the disease life cycle.

Management
There are no chemical controls at this time for wetwood. Occasionally a plastic pipe may be used to drain the slime flux in order to avoid additional weakening of trunk and branch crotches. Never use a metal pipe since the trees will eventually engulf the pipe. When the tree needs to be removed or trimmed, saws hitting the pipe may be damaged or worse the person using the saw may be injured or killed.
Credit

James E Schuster, retired Extension Specialist, Horticulture & Plant Pathology, University of Illinois

PathogenID
45
Images
Image
Wetwood symptoms at base of tree trunk.
picID
35090
Image
Wetwood symptoms on cut elm stub.
picID
33342
Image
Wetwood symptoms on tree trunk.
picID
35323
Image
Wetwood symptoms on tree trunk.
picID
35337
Image
White streak on elm bark due to wetwood
picID
31198
Image
Wetwood symptoms from cut branch.
picID
18437
Image
Wetwood symptoms from cut branch.
picID
18435
Image
Wetwood symptoms on tree trunk.
picID
18436
Image
Wetwood symptoms from cut branch.
picID
25803
Image
Wetwood symptoms on tree trunk.
picID
35331
Image
Wetwood symptoms on cut elm stub.
picID
35333
Image
Wetwood symptoms on tree trunk.
picID
35334
Image
Wetwood symptoms on tree trunk (Installation of a steel drain pipe is NOT a safe solution).
picID
35335
Image
Wetwood symptoms in the tree heartwood.
picID
35336