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