A lot of the time on branches that are starting to show new growth small circles like that will be the first signs of the growth. They are normally spread out and aefw bit marks will normally follow a trail. On the other hand they will do anything to fool you and make it into your system, almost like they know where to go so you can’t see them. Evil little worms. If nothing was in the dip I wouldn’t worry, I always keep my eyes opened anyways though.