FIRE BLIGHT

What is Fire Blight?

Fire Blight is a bacterial disease that is found most commonly in Crabapple, Pear, and Apple trees. In the early stages, all the leaves on smaller twigs will first appear water-soaked, then brown and bent downwards forming a “shepherd’s crook”, and finally appear to be burnt. Upon closer inspection of the larger branches or trunk, there may be cankers or ooze that contains the bacteria. There is no cure for Fire Blight but it can be treated, tree owners should look at practices to suppress the bacteria and minimize the spread to the rest of the tree or adjacent trees. Spreading happens most often during rainy seasons but is also translocated by insects.

Managing Fire Blight

Planting

The most effective step in preventing Fire Blight on your property is to take the time to plant the “right tree in the right place”. This will not be helpful to valuable trees that have been established for many years and are now showing signs. Before purchasing a tree from a hardware store or garden center on a whim, take the time to research resistant varieties, climate zone adaptation, and the local success of mature trees. Taking the time and possibly spending more on the correct cultivar will reduce headaches in the future and bring more enjoyment from the tree over time.

Pruning and Ground Treatments

Pruning out blighted twigs early in the stages, but not during springtime rains, 8 to 12 inches below any signs prevents the bacteria from moving to larger branches in the tree. Winter pruning a susceptible tree to reduce new rapid shoot growth can suppress fire blight and help shape the tree. Since new rapid shoot growth is more susceptible, nitrogen fertilizer should be minimized since it encourages above-ground growth in favor of plans that encourage root growth and microbe activity or even regulate shoot growth. Northeast Tree Care has some specialized ground treatments that will satisfy this goal for your crabapple, pear, or apple tree.

If the canopy appears to be 40% affected or more, the tree is most likely not worth saving.

Chemical Suppression

Northeast Tree Care can help make a plan for your tree with a variety of systemic injectable solutions or topical sprays before bud break. We will make sure to work with the tree owner to formulate a plan that is most effective, economical, and safe for each situation. Some chemicals that we can use to combat fire blight include:

• Arbor OTC - Injectable antibiotic

• Phospho-Jet - Injectable fungicide

• Bio MP - Increases Microbial activity

• Hydretain - Helps with Drought Stress

• Cytogro - Stimulates root growth

• Shortstop 2SC - Plant growth regulator

Please reach out to Northeast Tree Care for any help with managing a tree you suspect may have Fire Blight. Northern Colorado: 970-580-8773