Michigan State University Extension
Ornamental Plants plus Version 3.0 - 00001687
11/12/99
Russian Olive Canker and Dieback
The Russian olive is so susceptible to the canker and
dieback caused by Phomopsis elaeagni that it is no longer
considered suitable as an ornamental shrub or small tree.
Symptoms: Symptoms are a typical dieback of branches in
the uppermost portion of the canopy. Young green shoots
may wilt and die and leaves remain withered and attached.
The sapwood below the dead, orange-brown bark turns black,
and the discoloration extends beyond the canker. Cankers
are oval and depressed; most are 1 to 6 inches long.
Cause: The spores of the fungus are rain splashed and
generally infect broken thorns, branch stubs and bark
wounds. The fungus will infect even healthy, vigorously
growing plants. Infection can occur throughout the
growing season whenever rain and wounds are present.
Spores ooze from fruiting bodies on the dead, orange-brown
bark whenever rains wet the branches.
Control: Russian olives with dieback might best be removed
and replaced with the canker-resistant autumn olive.
Otherwise, prune out dead branches and revitalize the root
system as described under General decline and dieback. No
fungicides are effective for control of Phomopsis on
Russian olive.
This information is for educational purposes only. References
to commercial products or trade names does not imply
endorsement by MSU Extension or bias against those not
mentioned. This information becomes public property upon
publication and may be printed verbatim with credit to MSU
Extension. Reprinting cannot be used to endorse or advertise
a commercial product or company.
This file was generated from data base ZZ on 01/19/00.
Data base ZZ was last revised on 11/12/99.
For more information about this data base or its contents please contact
heatley@msue.msu.edu . Please read our
disclaimer for important
information about using our site.