From the Fit Farmer:
We often get questions about using hoop houses for portable chicken tractors. A basic hoop house structure can be built for this purpose. For the summer months, enclosing the hoop house with end walls made of wood or metal and covering the hoops with chicken wire or hog panels will suffice. Adding greenhouse plasticto the structure to extend into the colder months is also and option. Chicken tractors made from hoop house frames are portable yet sturdy. With an open bottom, the structures can be moved around to bring fertilizer right to where you need it.
More Hoop House & High Tunnel Building Guides:
Prequel to Starting a Build - Ground Posts - Bending Hoops - Hip & Base Boards, Ridge Poles & Purlins - Endwall Construction - Lock Channel, Spring Wire - Greenhouse Plastic Attachment - Inflating Double Layer Poly