Spanish moss (Tillandsia usneoides) This is a relatively easy way to remove Spanish Moss from your very tall trees without leaving the ground. It is fairly cheap, and if you have fairly normal strength, you can do the work yourself.
Years ago, there was an industry in Florida that used dried and treated Spanish moss to stuff mattresses. To gather the moss, they used long poles with hooks, and pulled it out of the trees. The suggestions below can help you design your own hooked pole, and the link can lead you to one company that sells telescopic poles for professionals.
Providing this service as an addition to tree trimming could be a lucrative side job.
The description below is for the homeowner who doesn't want to spend much money for equipment. This method is tried and true.
Purchase several 5' plastic plant stakes at your local nursery or Home Depot. Depending on how tall you want it, subtract two feet from the length of each pole, as you will be overlapping one foot for each pole on each end. Therefore if you want a 20' pole, get seven poles. They are not expensive, and they are very light weight and strong.
Overlap all the poles at least 12" end to end with duct tape. Make MANY loops with the tape for the whole 12" and press into the grooves. You want this very strong as you will be pulling on it. At the very end, place your BLUNT END hooks (this is for safety and will not get stuck in the tree) on the end and duct tape them very well also. Have the hooks facing 180 degrees away from each other as it is more effective. I used large screw-type hooks I purchased at Home Depot that were designed for who knows what. But the hooks should have a large opening for ease of hooking.
Your pole will wobble a bit, but not too badly. Place the hooks up into a mass of moss and spin or twist, as if you were making cotton candy. With a bit of practice, you will be able to get a good grip and yank the moss free. I cleaned both of my huge trees up to about 30' standing on the ground. For taller trees, the poles can be made longer.