C shows the shape of a drainage pattern. A is a tone and texture variation in soybeans caused by weeds. B is a texture variation due to weed growth where wet conditions caused planting problems. C is a tone variation caused by different soybean varieties. D is typical herbicide carryover.
E is a pattern caused by nitrogen applied at an angle.
A's are tone variations caused by different soybean varieties. B's are also tone variations but caused by different soybean varieties. C is a texture variation due to broadleaf weeds. D is a variation in texture caused by grasses. B is a tone variation caused by double application of nitrogen.