Question

what are crumbs? why they should be broken

Answer 1

crumbs are structures( like lumps ) that are left after phoughing due to the moisturized soil below the top soil. levelling is the process of breaking these lumps .

Answer 2

Crumbs are referred to as the large pieces of aggregated soil present as lumps. They need to be crushed and grounded and this is done while ploughing and tilling of land before land is prepared for sowing. This is done with the help of iron leveller or wooden plank in smaller areas or power tillers in large areas. This is done so that there is proper space for roots to penetrate, for better air circulation and good germination of seedlings.