The best way to put out this fire is to prevent it in the first place
Fire blight disease carries bacteria that affects mostly apple and pear trees.
It begins as cankers on the trunk and spreads to branches, shoots, and blooms.
Young trees can die from fire blight disease, while more mature trees can live with it for several years.
The best way to prevent fire blight disease is to plant tree varieties that are resistant to the disease.
You can treat fire blight disease by pruning affected areas and applying a copper-based protective spray.
Fruit trees are a luxury when they’re healthy, but when diseases like fire blight take flight, your precious trees can be at risk of dying or spreading the sickness like—pardon our pun—wildfire. Since it’s a detrimental disease, our guide helps break down how fire blight can grow on your trees and what to do to prevent it from forming.
Fire blight is a bacterial disease that impacts a variety of apple and pear trees. This particular plant disease gets its name because it leaves behind wilted and brown blossoms, shoots, and branches, almost like they’ve been burned by a fire. Fire blight thrives in warm, wet conditions and often spreads through insects, rain, and contaminated tools. Young trees affected by fire blight can die in a single season, whereas more mature trees can survive several seasons of fire blight.
Caused by the bacterium Erwinia amylovora, fire blight first presents as cankers on the trunk, main branches, or mummified fruit. Once it appears, it’s hard to stop this pesky disease because it can multiply rapidly. Other common signs of fire blight include:
Curling shoots
Blackening shoots
Dark water spots on blossoms or leaves
Oozing cankers on the trunk
If it’s too little too late and fire blight has already taken hold of your fruit trees, there are some steps you can take to try and nip it in the bud and keep it from coming back. If you’re uncomfortable taking these tasks on yourself, consider contacting your local tree maintenance professional to help.
First, you need to cut out any infected branches about 8 to 12 inches below the visible symptoms. Between cuts, remember to disinfect your pruning tools with a solution of 10% bleach or rubbing alcohol to prevent the bacteria from spreading.
The healthier your trees, the less likely they are to be overtaken by fire blight disease. You can improve your trees’ health by applying a balanced fertilizer regularly. Just be sure to steer clear of fertilizers with excessive nitrogen, which can make trees more susceptible to fire blight disease.
Fire blight thrives in warm, wet conditions, so you should prevent overwatering and water at the base of the tree to ensure proper drainage.
The best way to prevent fire blight disease is to plant resistant varieties of apple and pear trees. Some varieties are extremely resistant, while others are more susceptible to the bacteria fire blight carries. Below we’ve laid out which varieties to look for when planting an apple or pear tree to help prevent fire blight from developing.
Other effective prevention methods include pruning in late winter or early spring when conditions are dry and disinfecting pruning tools between cuts. Copper-based protective sprays can also help keep fire blight at bay when pruning trees.
| Most Susceptible Apple | Moderately Susceptible Apple | Most Resistant Apple |
|---|---|---|
| Beacon | Dutchess | Jonafree |
| Cortland | Empire | Melrose |
| Fuji | Golden Delicious | Northwestern Greening |
| Gala | Haralson | Nova Easygro |
| Granny Smith | Jonagold | Prima |
| Idared | Jonamac | Priscilla |
| Jonathan | Jerseymac | Quinte |
| Lodi | Liberty | Red Delicious |
| Monroe | McIntosh | Red Free |
| Mutsu | Minjon | Sir Prize |
| Paulared | Northern Spy | Pristine |
| Rome Beauty | Novamac | Liberty |
| Wayne | Spartan | Goldrush |
| Wealthy | Honeycrisp | Enterprize |
| Yellow Transparent | Braeburn | Sundance |
| Ginger gold | Winsap | Williams Pride |
| Most Susceptible Pear | Moderately Susceptible Pear | Most Resistant Pear |
|---|---|---|
| Aurora | Maxine | Kieffer |
| Bartlett | Seckel | Magness |
| Bosc | Beurre D’Anjou | Moonglow |
| Clapp’s Favorite | Harrow Delight | |
| Red Bartlett | Honeysweet | |
| Reimer Red | Blake’s Pride | |
| Starkrimson |
If your tree suffers from fire blight several years in a row, the disease is likely to continue coming back every year. If you have mature trees, this might not be a detriment as older trees can survive for years with fire blight. New trees, however, are more at risk of dying due to fire blight. It’s a good idea to work with a tree maintenance pro to help care for any sick trees.
No, fire blight does not survive free in the soil but instead is carried through insects, animals, rain, or wind during the spring. Keep in mind that it can also spread on tools, which is why you should always disinfect them in between cuts.
