Greenhouses - Raised Platform Design
Putting a growing enclosure up high can allow it to get more sunlight.
The design for this is not yet done. It involves an elevated wooden platform up in the trees, supported tree-house style from the existing trees. The main objective is to get more sunlight without having to clear a big area of forest. Being up high you also potentially get a nice view.
Use Garnier limbs (or equivalent) to attach to tree trunks.
When more than one tree is being used you need to use floating attachments http://www.treehousesupplies.com/Treehouse_Brackets_s/28.htm
Use 1-1/4" lab bolts http://www.treehousesupplies.com/Lag_Bolt_1_25x12_p/lb1.25x12gal.htm
If you plan to clear trees in a particular area, then you can mount a walkway and/or cabin/greenhouse on top of the cut stumps. They will rot over time, say 25 years, but until then they will form a good foundation. On a slope this is a good way of making a foundation as you are not disturbing the slope and thus avoiding erosion. Use a self leveling laser to determine the height of the stumps. Fell the tree just above this height and the do a clean level chainsaw cut at the exact laser marked height.