By the intensive mixing of organic matter with inorganic soil particles and microorganisms and by slime secretion, earthworms create stable soil crumbs, which contribute to a good soil structure. Soils with high earthworm activity have less tendency to become muddy and can be worked more easily than soils with low earthworm activity. In addition, nutrients and water are more effectively retained in the soil. Abundant worm casts production makes heavy soils looser and sandy soils more cohesive.