You didn't really think that a Christmas tree elf grew all of the world's Christmas trees and then dropped them off in a parking lot in the middle of the night for some dude with an axe to resell, marked up 200 percent, did you? If you did, that's magical and you should keep thinking that.
Or you can watch this recently resurfaced viral video of helicopter pilot Dan Clark harvesting trees at the Noble Mountain Christmas Tree Farm in Oregon. If you thought Santa was efficient (getting around the whole world in one night, etc.), just wait until you see Dan. He is efficient.
Fun fact from the video's description: "Oregon is the nation's biggest producer and exporter of Christmas trees, selling about 7.3 million trees a year [in 2011], more than twice that of No. 2, North Carolina."
Here is another amazing harvesting video, including the pilot's perspective:
A commenter over on Reddit explained the process (and how it's not as dangerous as it looks):
Pretty typical long line operation by a small helicopter with a skilled pilot. This video really shows the easy part of the job. The really hard work takes place on the ground....by the choker setters (those that set the choker cables on the groups of trees), the hookers (they attach the helo's long line hook to the choker) and the chaser (they remove the chokers from the load after it is dropped).
It can take hours of preparation on the ground (cutting and grouping trees and setting chokers) to get ready for the rapid movement of trees that you see in this video. Regarding safety, the flight track is kept clear of personnel in case of an inadvertent load drop, or in case the pilot needs to punch the load in case of an emergency.