Answer: Based on your description I am not sure what you are seeing. Without a definite identification of the problem, it is impossible to tell you what to do -- or even if it is something that needs to be controlled. These could be aphids for example, or possibly pear psylla nymphs feeding on the leaves, with black mold growing on the honeydew secreted by the pest. The pear psylla would usually be prevented by using an oil spray very early in the year, while aphids can be knocked down with a spray of water from the garden hose. As you can see, treatment can vary widely depending on which pest it is. I would suggest you consult with your county extension and get a specific identification of the problem. Then, based on knowing that, they can help you plan a regular spray program for your pear tree. Good luck with your pear tree!
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