What is fire blight? It is a contagious, systemic, bacterial disease, prevalent on apple and pear trees during cool wet periods of spring weather. I thought it would be good to share some ideas on how to recognize the disease and control the spread of it.
The bacteria attacks the blossoms in early spring and then starts to move up the branches through the trees system. The infected leaves, stems and bark will take on a scorched or burnt appearance thus the name “fire blight”. Blossoms will turn brown, wilt and die within 1 to 2 weeks after being infected.
Fire blight may exhibit an amber colored liquid oozing from the bark of the tree. This is heavy with bacteria. Temperatures in the range of 70 to 80 degrees create perfect conditions for the spread of the disease. The disease can be spread by birds, bees, insects, wind and even splashing rain.
The disease is most common on apple and pear trees, both fruit bearing or ornamental. It can also affect quince and other members of the Rosaceae family including rose and raspberry plants.
How to Control and deal with Fire Blight
The thing you are most interested in is how to control or deal with the problem. If you have heavy amounts of new growth on the plants it can be susceptible to the problem. If you live where the blight is a known problem I would suggest using a low nitrogen fertilizer during the growing season and only fertilizing when necessary. You may not need to use fertilizer at all.
Try to keep the area around your trees clean at all times. Be sure to give the area a good cleaning in the fall after all leaves are off the plants. As soon as you see any sign of blight bring out the pruners and clip the infected area off the tree. Cut back some 10 to 12 inches beyond the damaged area. Be sure and burn the clippings.
Do not put any clippings or dead leaves from cleanup into compost piles. This would offer ideal conditions for the disease to overwinter.
During the season remove all tree suckers or watersprouts since they are fast growing and tender they are vulnerable to the blight.
All tools used in pruning or around the plants should be disinfected as soon as the job is finished. Use a 10 to1 bleach mixture or use alcohol wipes. Dip clippers between every cut.
There are some approved chemical products on the market that can help control the problem. If you use chemicals they should be applied from bloom time to the end of the spring season. READ AND FOLLOW THE LABEL INSTRUCTIONS. DO NOT ASK THE STORE CLERK HOW TO USE.
There are some blight resistant plant varieties on the market you can try. Note, I said resistant, I did not say they were totally blight proof. You need to still provide routine maintenance. Fire Blight is a tough disease is not easy to control. There is no one practice that will cure the problem. You will need a combination of the above.