Essential Collection of Sericulture, Volume Two

Foul-smelling Leaves

If mulberry leaves are allowed to ferment The original term is "steaming" (fazheng), referring to the natural heat and moisture buildup in a dense pile of green matter. for a long duration, they will turn black and develop an odor. The Essentials of Agriculture and Sericulture A major agricultural treatise compiled during the Yuan Dynasty. states: "Leaves that are damp and foul-smelling will cause various diseases; silkworms must never be allowed to eat them."

Generally, when harvesting leaves from distant locations and transporting them by boat, the leaves are most prone to becoming overheated and fermented. Halfway through the journey, one must select a cool, shaded spot to take the leaves out, spread them loosely to air, and then reload them onto the boat. This process is called "releasing the heat" The character "heat/baking" (hong) is formed from the phonetic components hu and gong This is a traditional Chinese fanqie pronunciation guide.. This term implies that the fermented leaves are as hot as if they were being baked; they must be brought out to cool, otherwise they will turn black and foul.

Hot Leaves

If leaves are harvested and bundled during the midday sun, they will be hot. If the leaves are piled up and allowed to ferment, they will also become hot. Silkworms have an aversion to eating such leaves. In either case, the leaves should be spread out and aired on cool ground to dissipate the trapped, sweltering heat.

Wilted Leaves

The Essentials of Agriculture and Sericulture says: "Leaves withered and dried by the wind and sun cause abdominal blockages A condition where the silkworm's digestive tract becomes obstructed, often fatal.."

Silkworms should be fed fresh leaves. If leaves are kept overnight, their vitality and nutrients Literally "fat" (zhi). dry up. If they are withered by the wind, their juices will be parched. Silkworms will not eat these, and they should be discarded.