Toyon Can Develop Fireblight Since it is in the Rose Family

Q.
Does this look like fireblight disease to you on established toyon? Toyon is in
the rose family of plants.

Toyon can catch fireblight bacterial disease in the spring and summer months.

A.
Toyon is a California native plant in the rose family and related to Photinia. Both
plants are susceptible to fireblight. When the plant is dead it can be hard to
say. Sometimes susceptible plants only lose their flowers and sometimes the
entire plant dies. With prolonged wet weather this disease can be vicious. Sometimes
plants “linger” with this disease, and it can lie dormant until cooler and
particularly wet weather.

Fireblight bacterial disease on new spring growth.

            Look for bacterial “ooze” coming
from wounds. This “ooze” are wet spots on tree limbs or the trunk. During wet
weather this ooze may attract insects. Observing this plant can be a good way
to know otherwise you have to send it to a plant pathologist and know for sure.
Best way, when in doubt, is to assume its fireblight and remove it and get the
dead plant off the property before it has a chance to spread. Be sure to sterilize
any pruning equipment when you are finished.

Fireblight on Asian pear in early summer