While inspecting [another problem][1] I observed that most of the leaves are having two red dots (or very small bulbs, maybe cocoons) at the stems of their leaves: it is something harmful or even a pest? If so, do I need to do something?

![][2]


  [1]: http://gardening.stackexchange.com/questions/4732/leaves-at-the-tip-on-new-branches-of-my-cherry-trees-are-wrinkled
  [2]: https://i.sstatic.net/r4RGO.jpg