Question
I have about 15 pears lining my driveway (about 6 feet from the ashpalt) - they were installed 2 falls ago.  all are doing well but a number of them have localized browning and wilting of the leaves.  the browning is localized to just a few branches and not the entire tree,  it is as if the small branch or limb just died -

is this fire blight or just a weak limb?  should i remove them?

i have noticed that other pears in the neighborhood are having the same symptoms and are much older trees.

thanks

B

Pittsburgh, Pa.

Answer
Brett:
Could be fire blight as you mentioned. This is a significant bacterial disease problem in this part of the world on these trees.  Ornamental (Callery) have some real health/structural issues- despite the fact they have some nice characteristics as well.  FB looks like someone put a blow torch to the ends of the branches- leaves dark brown to black, looks scorched. Random/scattered branches become affected. IF THIS IS INDEED FB, it will continue to spread down that particular branch toward the main central trunk (especially during the spring when rain is frequent).  Best to prune it out as soon as you suspect that it is FB. Locate the area where the dead portion meets the green portion on a branch.  Go back 6-8 inches into the green to make your cut.  Do this pruning when branches are completly dry. Sanitize your pruners with rubbing alcohol between each cut (1-2 minutes). Destroy the branches that you prune out. You can spread the bacteria on your pruners.  Sprays with antibiotics can be useful, BUT they have to be applied at a specific time and they must cover the entire tree.  Multiple applications usually necessary too.  This is usually not practical/feasible for homeowners, so pruning is the best option.  Sometimes it is impossible to prune it all out because of the numbers of branches and size of the tree.

The bacteria usually infect those open flowers in the spring.  Bacteria are often carried to the flowers by bees that pollinate-- the bacterial usually hitch a ride on the insect. Bacterial can also move from one branch to another by splashing water/wind.

Google some images of FB to see if they resemble your situation. Some cultivars of ornamental pears are more susceptible to FB than others.

Let me know if you need any additional information.