Mulching (called Gurneyism in England) consists in covering the soil with salt hay, litter, seaweed, leaves, spent tanbark, chips, or other refuse matter.
Every farmer must have noticed that, if a board or rail, or an old brush-heap be removed in spring from soil where grass is growing, the grass afterwards grows in those places much larger and better than in other parts of the field.
This improvement arises from various causes.
1. The evaporation of water from the soil is prevented during drought by the shade afforded by the mulch; and it is therefore kept in better condition, as to moisture and temperature, than when evaporation goes on more freely. This condition is well calculated to advance the chemical changes necessary to prepare the matters—both organic and mineral—in the soil for the use of plants.
2. By preventing evaporation, we partially protect the soil from losing ammonia resultant from decaying organic matter.
3. A heavy mulch breaks the force of rains, and prevents them from compacting the soil, as would be the result, were no such precaution taken.
4. Mulching protects the surface-soil from freezing as readily as when exposed, and thus keeps it longer open for the admission of air and moisture. When unprotected, the soil early becomes frozen; and all water falling, instead of entering as it should do, passes off on the surface.
Why does mulching take the place of artificial watering?
Why is the late sowing of oats beneficial?
From what arises the chief benefit of top dressing the soil with manure in autumn?