Our peach tree has been having a bit of a rough time this year. It has been affected by a fungus called "peach leaf curl", so it has lost many leaves and we also had to remove all of the fruit that was starting to grow. This will allow the tree to focus its efforts on healthy leaves, rather than producing fruit.
More recently, I noticed these strange circular black things all over the tree. Sort of like little black half-balls, a couple of millimetres big, clustered in various places around the tree. When I pick them off, they're sort of squishy and juicy. Still not sure what they are. Any ideas?
UPDATE: This is a form of fruit tree scale. Typically controlled by washing, horticultural oil spray, etc.