no its not a new measurement of speed, although that would be pretty funky, its how many trees will be spawning every hour during the event.
Why am i telling you this?

Well each tree will be dropping between 1 and 4 items a go, so that between 3,600 and 14,400 item an hour being pushed in to to the game. So as a result the presents will not be giving items every time, in fact the items giving will be pretty tight tbh, but don’t lose hope, as you will hopefully get a rare @ some point.

Trees will be in for a week, then will be halloween event.

/Lapta