Ask a Consulting Arborist Q&A: Bark and Trunk Concerns

Q: A couple of Italian cypress trees are "leaking" sap and don't look healthy. Can they be saved??

Wednesday, December 30, 2015  

Q: A couple of Italian cypress trees well over 20 feet tall are "leaking" sap and don't look healthy. Can I save them in this state or would it be best to remove them?

A: Italian cypress are susceptible to common diseases, including Phytophthora, Armillaria root decay fungi, and Seridium canker. The oozing may be an indication of Seridium canker. Have you made changes in your irrigation practices with the drought water restrictions in California? Reduced water has initiated many tree disease issues and tree loss in California.

One Seridium canker symptom is browning of individual branches. Often, only one or two limbs initially exhibits symptoms, but following favorable weather periods (warm, humid periods or rain) and time, the disease may spread so that many limbs are affected. If the shoots are followed down toward the trunk, a resinous oozing canker may be observed. Dead and browning branches will not return to life and can be pruned off to slow the disease spread. Tree removal decisions may be based on appearance after pruning, the ability to phase replacement versus starting over, and resources.

There are no simple recommended chemical controls available to treat Seridium canker. Tree owners should maintain health and vigor by irrigation during periods of drought. Irrigation should not spray the trunks and low foliage, but rather soak into the soil. Also, keep the base of the trees clear and unburied. Infected pruned branches should be removed and discarded (do not home compost). Severely affected plants should be removed from the landscape to prevent spread of the disease to other healthy plants in the area. Resistant replacement species should be selected if removing some trees in larger planting or replacing feature trees.


Responder: Gordon Mann, RCA #337, Fort Wayne, IN