Tree Crops: A Permanent Agriculture by J. Russel Smith – This far sighted book was written for American audiences in 1929. It encourages use of fodder trees to stabilize the landscape and provide nutrition for stock. This double cropping of the land is encouraged by Tree Crops, and the book’s principles and examples are still current today. The language, being nearly a century old, is at times not as easy to read as a modern book. But it has many photos and overall worthy of being more widely read.