Question
my ornamental plum tree has gone dormant (or dead) for no apparent reason.  we are a month past bloomimg seasona and the tree has what looks like buds, but has yet to bloom or bud leaves.  no sign of disease and was very healthy last year.  Tree is only 6-7 years old.  what could be wrong.

Answer
Maureen:
I am not aware of an insect or disease that could do this so quick as you describe. This may have been delayed by a period of cold weather or other environmental stress.  Consider examining the trunk, especially near the soil line.  Look for any loose bark or injury, or holes in the wood.  These may offer some indications.  Also try scratching a few of the "bare" twigs with your fingernail. Look for green beneath, which may indicate that it may yet bud out.

Regards
Steve