I'm about a year late to this thread but...
We are using our own variation of Mark's mass planting STUN system in middle Tennessee. In one area we have planted with swales or berms and basins and in another with brush berms. The land was logged so we have done random planting of natives in other areas as well. The distance between the trees is about 2 feet apart, sometimes closer. We are also using it to create enosculated fedges, hedges, living fences by planting even closer. We have planted over 3500 bareroot trees and shrubs this way using the same quick method that is used by foresters and have gotten pretty dang fast at it!
If you want to find inexpensive bareroot whips and seedlings look to Warren County/ McMinnville, TN "the tree nursery capital of the world" as they call it. There are over 300 nurseries there, some good some not so good as we are discovering. 12inch bareroot seedlings average around .60 cents each. The more you buy the cheaper it gets.
We bought from our state nursery this year as well for the first time and I'm impressed so far. When we picked up our bareroot trees we got to see the seed orchards that were planted in the 1950s and 1960s which was pretty cool.
Warren County TN nurseries have a terrible, incomplete website but here it is anyway:
http://www.tnnursery.com/
The highest berm and basin system we have (top of the hill) is pictured below right after it was made and planted. You can kinda see how close the plantings are for the hedge here (mainly hawthorn, mimosa, bush clover and some plum and crab apple). To the left there are some more berm/basins. This is all on the top of the hill to slow the runoff on this huge surface area and sink it before it really starts to slope off. Then below that, out of frame on the hillside, there are 3 long swales wrapping around the contour of the sloped hill with mass plantings.
Sorting trees for planting, Spring 2015: