I have hundred foot tall trees I want to get lights on the top of. How?

One of my friends used an RC toy helicopter to get lights up into the tops of trees in front of his house. He attached a long loop of string using a slip knot to the copter and flew it up and around the top of the tree until the string snagged on a limb and pulled loose from the copter. Then he tied the lights to one end of the string and used the other end to pull them up to the top of the tree. You have to make sure the string is twice as tall as the tree and BOTH ends hang down to the ground to do this. You might also be able to get string up there using helium balloons. I would use two of them, tied together with 3 to 6 feet of string and with a 100 foot or longer string on each one, that way you can steer the balloons until the strrings catch on the tree. I would drape a 200' piece of string over the short string connecting them -- this is what you would use to haul the lights up to the top once you got the balloons and their harness tangled in the branches.

Are you SURE these trees are 100' tall? that is the height of an 8 story building or 3 to 4 times the height of the average house.

Commercial holiday lighting installers typically use boom trucks, the articulated arms with a basket on the end that workers can stand in, like those used by electrical and phone line workers. You can rent them but you need to demonstrate knowledge of how to use one first. Or you can hire a contractor who owns one, but it will cost hundreds of dollars for just a few hours.

An aluminum roof rake would probably be long enough. They are lightweight and have a 3 ft detachable plastic plow at the end that you will not need. You fasten a hook to the end and lift the string of lights from the middle of the string up to the top.

These have 6 foot extension tubes that can be added as needed. To reach a 100 ft you may need to buy another roof rake and use the extensions supplied. Also with this length you will need to keep it as vertical as possible as you lift so it will not bend under the added weight.

Obviously, they are for snow but it suits this purpose also. It is safe because there are no ladders and you can drape the string around from the tree safely.

Don't try plugging them into a power source until you are finished with stringing the lights.

I would say the best application is from top down and not circling the tree to avoid tangling issues.

LED are certainly preferred due to low wattage, light weight and easy application.

Jump. Or you will have to call a tree service. Have you watched the Christmas movies? Be careful, and Merry Christmas.

Get a crane; I mean something similar not exactly a crane but a truck rather that lifts men up....

If you get what I mean

hardcore parkour.