Here's what the tree looked like before:
|Close up of a blighted leaf|
The treatment involves removing the infected areas of tree. Cuts must be made 6-12 inches below infected area (huh, that's kind of a large margin, let's go with 12). Signs of infection can be blight leaves, canker-looking bumps, or wood that looks burned. The shears must be disinfected after each cut with bleach (this stuff is tough). After all infected areas have been removed, mix a little sulfer with some water and spray on tree. Sulfer will prevent anything from getting onto the tree by killing it.
Sulfer water is pretty bad stuff. If your skin comes into contact with it, you have to wash it for 20 minutes. If it gets on your clothes, put them in the wash immediately. Getting it in your eye or ingesting it - bad news bears. I can't help but remember the saying, "Only pick fights you know you can win." I'm starting to have some doubts.
Here's the tree after we removed all the diseased wood:
Amputation is the only treatment, which makes for one sad looking, Charlie Brown pear tree. There are some antibacterial drugs out there to kill fire blight, but (over) use has caused drug resistent strains to form, so those are hit-and-miss now. If we're lucky, we'll have removed all of the diseased wood and the tree will recover. If not, it'll die. If that happens, we'll try again with a new tree, but we'll have to remove all the soil from the original tree because it might pass fire blight onto the next one.
Is it too late to ask the fire blight for a cessation of hostilities?