Measure the lengths of all the strings of
lights that you will use on the tree. In the U.S. most
strings are 25 feet, consisting of 25 lights at one foot
intervals. On the left side of the table below, for each
string of lights, enter the lengths and select inches, feet,
cm (centimeters) or m (meters). Now get a measuring tape and hold one end of it to the pinnacle of your tree. Stretch the tape out to a point on the bottom edge and the note the measurement. It is better to measure this in inches instead of feet. On the right side of the table below, on the line for your last string of lights, type that measurement and select inches, feet, cm or m. The measurement boxes for the other strings of lights will be filled-in automatically for you. For those boxes, you may select inches, feet, cm or m, and the measurements will be updated accordingly. For example, if your tree is 60 inches long and you have 4 strings of lights, 25 feet each, enter 25 and select feet for the first four lines on the left side of the table. Then enter 60 and select inches in the box for the 4th string of lights on the right side of the table. The first three string measurements will be automatically filled-in with 30, 42.43 and 51.96 inches, if you have selected inches for each of these. The numbers tell you where to end each string of lights relative to the pinnacle of the tree. As you are winding lights around the tree, start from the top and try to spread out the lights so when you get to the end of a string of lights you are at the indicated distance from the top of the tree. If you are planning to do this next year with the same tree and lights, get a piece of rope and stretch it from the top of the tree to the bottom and mark the spots where each string of lights should end. Save the rope for next year. But next year don't hold the rope upside down! The marks are more widely spaced toward the top of the tree (for equal length strings of lights). Yeah, you can use this tip even if you don't like the rest of my procedure. You're welcome. |

Here is the procedure: hold one end of the measuring tape (or marked rope) to the pinnacle of the tree and stretch it downward. Wrap lights starting at the pinnacle.

The idea is that the lights cover area whereas the measuring tape or rope covers distance, no matter how tall or wide the tree and no matter what units (feet, cm, etc.) are used to measure the tree. The computation here assumes the given lengths of light strings cover a constant width to illuminate area. It squares the measured distance along the side of the tree to get proportional area, scales to the proportion of total illuminated area relative to area above a given point on the tree, then takes the square root to convert area to distance.