From AMLopedia
Bush Jumping was invented in 1998 when the AML crew decided to jump through the bushes between the GTE House and Marcus' House. They experimented with different things, such as jumping through the bushes onto a mat and being stuffed into a gray recycling bin and being thrown through the bushes.
They finally filmed several Bush Jumping adventures, which can be seen in the Bush Jumping part of AML: Hardcore Revolution.
The next logical progression of bush jumping, pioneered by Adam, was box jumping. He would often take big boxes and jump onto them. Examples can be found in AML and AML 2.