Sodic soil: Sodic soils are high in certain forms of sodium. They are impermeable to water; puddling and runoff are common. Sodium hydroxide (caustic soda) in sodic soils dissolves organic matter, which becomes suspended in puddled water, turning it brown or black. For more information about sodic soils, see Salty Soil.

Heavy soil: Heavy soils are those with a large proportion of clay. They crack and are very hard when dry, and are sticky and difficult to mix or turn over when wet. To determine if your soil is heavy, dig a hole 2 feet deep in a poorly drained area. Fill the hole with water. If the water level drops more slowly than 1/10 inch per hour, heavy soil is probably causing your problem. Runoff and puddling may be reduced on heavy soils (and other poorly drained soils) by applying water more slowly. Use sprinkler heads with a lower water output, or oscillating or impulse hose-end sprinklers. Or cycle sprinklers by pausing for half an hour when runoff begins. For more information about heavy soil, see Heavy Soil.