Soil Improvements (Historical Marker)

Here follows the inscription written on this trailside historical marker:

Soil Improvements
"When I speak of a knowing farmer, I mean one who understands the best course of crops; … and above all, Midas like, one who can convert everything he touches into manure, as the first transmutation towards Gold."
George Washington to George William Fairfax, June 30, 1785

Washington knew from observation and experience that over planting the land depleted the soil of nutrients. In addition to animal manure and "green manure," such as buckwheat and clover, he used other natural fertilizers including:

Creek mud, which had rich nutrients similar to those provided by animal manure.

Fish heads, which provided nutrients and organic material as they decomposed in the soil.

Marl, which was described at the time as "chalky clay." Today we know marl is similar to lime, which is used to lower soil acidity.

Plaster of Paris, which is made chiefly of calcium sulfate or gypsum. Still used today, gypsum loosens heavy, clay-like soil without changing its PH balance. It also adds calcium and sulfur, both of which are important to plant growth.