Vegetation of Many Types
Not only is the soil of Mr. Burbank's garden at Santa Rosa enormously productive, but its various parts are adapted to vegetation of various types. By adding sand here and clay there, the character of the soil has been modified, to meet the needs of different kinds of plants; and it may well be doubted whether any other four acres of the earth's surface has grown a greater variety of plants. Certainly no other corresponding plot has grown anything like the same number of species within the same period of time.
This image is from: Luther Burbank: his methods and discoveries and their practical application. Volume 12 Chapter 2