Question: There are two or three dead limbs in my pear tree. A couple of weeks ago they were green and alive, but now their leaves are black. They’re just hanging on the limbs. What causes that?

Answer: That’s probably fire blight, a common visitor to Texas pear plantings. You must have a variety that is susceptible. Should fire blight kill an entire limb during the growing season you should remove the dead portion, cutting back into the living tissues by several inches. Disinfect your pruning tools between each limb that you cut, to prevent spread of the bacteria. Use a diluted solution of chlorine bleach (10 percent bleach, 90 percent water). Rinse and oil the tools after the final cut to prevent rusting.