• residential and commercial tree trimming and pruning services

Crabapple Fire Blight

Fire Blight is spreading like “wildfire” after two years with warm, wet springs.

Fire blight is a bacterial vascular infection of apples, crabapples, pear, Hawthorn and European mountain ash. It affects pome fruit trees (trees that bear fruit such as apples or pears, consisting of an outer fleshy layer and a central core) but not trees that bear stone fruits like cherry, plum or peach. With 2014 and 2015 came two consecutive years of unusually warm, wet springs and early summers. Unfortunately, fire blight thrives in these conditions and the spread of this disease has increased dramatically. Symptoms begin with water-soaked looking flowers and leaves, with the leaf petioles and branch tips bending into a “shepherd’s crook." Leaves of infected branches turn brown and the bark turns black, giving them the appearance that they are burned (hence the name fire blight). Email at info@dlcarbor.com or call us at 303 378-8000 today if your think your crabapple trees are sick.

Misinformation regarding fire blight is widespread, and many experts continue to disseminate decades-old falsehoods and outdated recommendations. Statements like “there’s no control for fire blight," “Tools must be disinfected between cuts” or “Crabapples can only be pruned in the winter” are false and have been disproven in both the laboratory and in practice. It is now understood that crabapples have some natural resistance to fire blight and the location of the pruning cuts is more important than the time of year and the disinfecting of tools. The treatment and knowledge about fire blight changes and improves almost as quickly as it does with human medicine.

Fire Blight Treatment

DLC Arbor has experienced great success curing Fire Blight in trees with less than 40% of the branches infected by utilizing a combination of trunk-injected antibiotics, autumn low-nitrogen fertilization and sanitation pruning. Treatment can begin quickly after our arborist diagnoses the disease – there’s no need to wait for months while the disease infects even more of the branches.