Post on craigslist and have people come dig them up for you. Seriously, you could at least offer to some friends - you may get more takers than you think.

By the way, why do you want to clear a steep slope of vegetation? Clear off too much and you'll have an erosion problem on your hands.

I don't want to clear the slope of vegetation; I want to get rid of the rotted trees and invasive species. I would like to terrace the slope so that we don't have an erosion problem and plant effective and attractive ground cover. Part of the hill has been terraced, but it is so overgrown, I can't tell what the topography truly is. It used to be literally impenetrable, with scores of volunteer trees 20'-30' high and enormous blackberry stands. Ivy and blackberries are considered invasive in our town, and my yard is a great illustration of why. I don't mind the ferns, but I don't want hundreds of them on a tiny lot. Thanks for your input.