mass noun
1- a material (such as decaying leaves, bark, or compost) spread around or over a plant to enrich or insulate the soil覆盖料（为肥沃或保护土壤铺在植物四周或上面的腐叶、树皮或堆肥）。
1.1
- count noun an application of such a material（覆盖料的）铺覆：
regular mulches keep down annual weeds.
定期铺覆盖料可抑制杂草每年的生长。
1.2
- a formless mass or pulp无定形的一堆; 浆状物：
a mulch of sodden brown stems.
一堆湿透了的褐色枝干。
词源
mid 17th cent.: probably from dialect mulch 'soft' used as a noun, from Old English melsc, mylsc.