What a man needs in gardening is a cast-iron back, with a hinge in it. – Charles Dudley Warner, My Summer in a Garden, 1871

Be it deep or shallow, red or black, sand or clay, the soil is the link between the rock core of the earth and the living things on its surface. It is the foothold for the plants we grow. Therein lies the main reason for our interest in soils. – Roy Simonson, USDA Yearbook of Agriculture, 1957

We know more about the movement of celestial bodies than about the soil underfoot. – Leonardo da Vinci