A list of the most important books ever written about sustainable agriculture (and human health) would include Tree Crops, as well as the books by Sir Albert Howard, the publications of William Albrecht and Price's Nutrition and Physical Degeneration.
Originally a series of four magazine articles appearing in The Country Gentleman, and later, responding to popular demand, published as a small book by the author himself. Explains in very few pages the way to achieve a permanent agriculture.
Krasil'nikov found ways to improve plant growth and crop yields with special composts and microbial ferments of the sort that could be produced by the farmer in an old barrel. All these "primitive" solutions are based on a very high-level understanding of soil microbes and how crop species interact with each other via long-lasting soil residues (root exudates), and how plants and microbes interact with each other.
Chapter I provides what may be the best basic soil's manual ever written; Chapter III shows how to grow plants with an awareness of their root activities. Also of particular interest are Weaver's frequent mentions of Albert Howard's researches in India.
A classic of farming lore and practice from the golden era of the Roman Empire. Scholars usually call this book De Re Rustica (On Agriculture). A Critical English Translation by Andrew Dalby.
Faulkner's book created a flurry of popular interest in alternatives to "scientific" agriculture. It is probably most important for what happened in American consciousness because of the interest it created rather than because of what the book says.
Henderson shares his lifetime accumulation of efficient farm methods, animal handling, including detailed instructions for newbies involving how to do physical work. Numerous photos and drawings.
How spreading aglime in far larger amounts than conventional ag science calls for greatly reduces the need for fertilizer and grows crops with much higher nutrient-density.