Search pole hedge trimmers or Extended Length Hedge Trimmers as below. There are some extended trimmers out there but I h/n seen or used any personally. Post a pic of your challenge. I have one neighbor with a similar challenge across his back. I assumed he used a ladder for the top and walked the sides with a nice gas powered 36" reach. The transfer of power at an angle would be my concern. I'm sure someone has a proven system. loger

STIHL Extended Length Hedge Trimmers link below:

http://www.stihlusa.com/hedgetrimmers/extendedhedgetrimmer.html

Stihl, Echo and Redmax all make articulating extended reach hedge trimmers, some with a shaft as long as 59". They're all excellent brands. I imagine any of them would work well for you. I've got several Stihl products I'm happy with, but Echo has a good rep and has a 5 year warranty. Redmax is probably the most expensive of the three. I was sitting at a Jiffy Rip the other day eating a snack in my truck and was watching a landscaper trim the hedges along the road. He had an articulating Redmax. He was zipping through those hedges at a pretty fast clip. I caught him walking back to his truck on my way out and asked how he liked the Redmax hedge trimmers. He said they were the best ones he'd used. That's just what one guy told me, and I have no personal experience with gas trimmers of any kind, so take that for what its worth.

thanks for your replies. I will research those listed.