Fireblight

Fireblight is a very damaging bacterial disease that affects various plants of the rose family.

What does is Affect?

In Alberta, many ornamentals and fruit-producing species can be affected, such as:

• Apple;
• Crabapple;
• Hawthorn;
• Raspberry; and
• Saskatoon.

What to Look For

Fireblight has distinctive symptoms that may appear on various parts of the plant that are infected:

• Leaves will turn brown or black, and twigs will curl;
• Blossoms can quickly become blighted and turn brown; and
• Material will have the appearance of being burned     

Prevention

There are best practices that you can follow to help manage Fireblight in the dormant and growing season.

In the dormant season:

• Cut out the cankers about 15-30cm below the canker margins in the growing season;

• Remove infected branches as soon as they are spotted, and be sure to prune them a minimum of 30-40cm below the visible area of infection;
• Continue to monitor every few days for new infections;
• Avoid over-fertilizing trees as excessive root growth is more susceptible to infection;
• Avoid any overhead sprinklers/irrigation; nd
• Certain chemical and biological controls are recommended for preventative use.

Related Links

• Agri-Facts Fireblight
• Fireblight - Government of Canada
• Fireblight - ATTS Group
• Fireblight - UMN Extension