Explaining the tree

FULL TREE: Used in Competition, Stock, and Super Stock, for which a handicap starting system is used to equalize competition. The three amber bulbs on the Christmas Tree flash consecutively five-tenths of a second apart, followed five-tenths later by the green starting light. A perfect reaction time on a full Tree is .000.
PRE-STAGE INDICATOR LIGHTS: Yellow bulbs warn drivers that they are approaching the startling line and the �staged� position.

STAGE INDICATOR LIGHTS: Signal drivers that they are on the starting line ready for a run. These yellow bulbs come on when the front wheels of a race car interrupt the beam from a light source to the photo cells. These same photo cells start the timing equipment.

THREE-AMBER STARTING SYSTEM: All three amber floodlights in a driver�s lane flash simultaneously before the green light comes on. This is called a �Pro start� system. Racers running in handicap categories get a countdown of one amber light at a time until the green light comes on. The Pro start system runs with a .4-second difference between amber and green lights, while the handicap system runs with a .5-second difference between bulbs.

GREEN LIGHT: This is the one that makes it happen. Once the green light is flashed, the driver in that lane is free to make a run. Any time a green light is shown in a driver�s lane it indicates that a fair start was accomplished.

RED LIGHT: When a car leaves the starting line before the green light comes on, or, in some cases, is staged too deeply into the staging beams, the red light will flash in that lane. It indicates the driver in that lane has been disqualified. During competition, only one red light will illuminate, thus eliminating only the first offender.