For example, coarsely textured, or sandy soils, allow water to enter and pass through more quickly. Aggregates can be as small as a grain of sand or as large as a pea. Organic matter promotes stabilization of the aggregate particles. Decaying organic matter acts like a glue to hold soil particles together, much like flour moistened and used as paste. Unnecessary digging or rototilling may break down aggregates into a fine powder, reducing pore space.
Soil structure is more important than texture, color or parent material.
It is also more important than any fertilizers that can be applied. Good soil structure allows water and air movement, and it provides channels through which roots grow. Overworked, poor soils show a very indistinct soil structure. Aggregates do not exist, so there are few air spaces between particles. Roots can suffocate and die where large amounts of water have forced air out of the space.