Christmas Tree

A Christmas Tree is the vertical electronic starting system used in drag racing that displays a sequence of colored lights to signal when drivers should launch their vehicles down the track.

The device gets its nickname from its appearance—a tall tower of brightly colored lights that resembles a decorated Christmas tree. This starting system stands between the two racing lanes at the starting line, where both drivers can clearly see it from their cockpits.

The Christmas Tree features several sets of lights stacked vertically. At the top, you'll find blue staging lights (or small amber lights on older models), followed by three large amber countdown lights, a green start light, and a red foul light. Each driver has their own column of lights on their side of the tree.

When approaching the starting line, drivers first trigger the pre-stage light by rolling their front tires through an electronic beam. This top blue light tells them they're about seven inches away from the official starting position. Rolling forward slightly breaks a second beam, lighting the stage indicator and confirming the vehicle is properly positioned at the starting line.

Once both drivers are staged, the countdown sequence begins with the amber lights. In a "Sportsman Tree" start, the three amber lights flash one at a time, each half a second apart, before the green light appears. In a "Professional Tree" start, all three amber lights illuminate at once, followed by the green light just four-tenths of a second later.

The green light means go—it's the official signal that the race has started. However, if a driver releases their brakes and moves forward before the green light appears, the red light illuminates on their side. This red light indicates a foul start, which typically results in automatic disqualification from that race, regardless of who crosses the finish line first.

Reaction time is everything in drag racing. This measurement shows how quickly a driver responded to the green light by leaving the starting line. Professional drivers can achieve reaction times as quick as four-hundredths of a second, demonstrating the incredible reflexes required at this level of competition.

The Christmas Tree was invented by Leo "Pat" Purcell in the early 1960s, revolutionizing drag racing by replacing inconsistent flag starts with precise electronic timing. This innovation made starts fairer and more exciting, as races could now be decided by thousandths of a second. Today, the Christmas Tree remains an iconic symbol of drag racing, and mastering its timing sequence is essential for any competitive drag racer.