Good privacy shrub/tree in a shady, heavily wooded area?
I just put up a stockade fence around my home, which includes an acre of forest (mostly huge oaks w/ 3ft+ trunks). The fence, due to falling branches, weather, age, and rambunctious neighbors, will last 15 years at most. Meanwhile, I was hoping to plant a row of privacy (also for property marking purposes) trees/shrubs/hedges right up against the fence, so that said shrubbery can replace the 6ft fence within 15 or 20 years.
What can I plant that can:
-grow in 100% shade
-grow in heavily wooded areas (I've cut down most of the smaller trees)
-serve as a privacy hedge in 15 yrs
-GROW WITHOUT MUCH CARE (I'll be away a lot)
Any help or suggestions would be much appreciated!