Question
Just had a chanticleer pear tree planted.  There were several branches with black leaves. Over the week more leaves have turned black and "clammy". The tree is in Colorado, and it is June so the leaves haven't frozen.  What is the cause and what is the solution?

Answer
Judith:
If the leaves appear as groups of brown/black leaves often on the ends of the branches, this may be a bacterial disease called Fire Blight.  Many plants in the same family are susceptible to FB. It is usually worst following a wet/cool spring. Trees can be sprayed with an antibiotic, but it must be during blooming only- otherwise pruning out the dead stuff is best.

See this bulletin that I have prepared on FB.

http://www.uaex.edu/Other_Areas/publications/PDF/FSA-7534.pdf

We have ornamental pears, fruit bearing pears and apples that get it here. There are some trees that have resistance to FB.
Regards
Steve