What Are the Causes of High Moisture in Corn?

Weather and Climate

• The most visible factors, the relative amounts of rainfall and heat from the sun, have an effect on the degree of held moisture at harvest. Ideally, a wet spring offsets a hot, dry summer in terms of moisture. The scorching sun of summer triggers increased water usage by the corn plant, and high precipitation levels during the months immediately following planting, give the soil an adequate supply to meet summer demands. However, a long stretch of wet weather through the summer months results in excess moisture taken up from the ground and trapped in the crop due to lack of sunlight and heat.

Breeding

• As an excess of moisture creates storage problems, a dearth of moisture creates growing problems. The advent of drought-resistant hybrids has addressed -- and continues to address -- the low moisture issue. Yet the enhanced ability to retain needed moisture during drought can also hold on to superfluous water when rainfall is plentiful. Likewise, some breeds grow ears that hang from the stalk, the force of gravity compelling rain to run off the ear, whereas other breeds' ears stand erect, catching the precipitation. Moreover, ear size varies from breed to breed, and the shorter, stockier ears experience a quicker dry-down prior to harvest than do longer ears with smaller circumference.

Soil Types

• Different compositions determine the actual water-holding capacity of any given soil. The plant, therefore, can drink from a larger or smaller supply, depending on the soil type. A soil dense with sand and gravel, for example, can carry only .02 inches of water for every .06 inch of soil. By contrast, a loam that is composed of relatively equal amounts of sand, silt and clay holds .17 inches of moisture within a soil sample of .23 inches. A rich soil like this provides more moisture to the corn stalk, its ears and kernels. The depth of the plant's roots also factor into how much moisture it draws from the ground.

Irrigation and Drainage

• While moisture in the earth affects moisture in the corn, the processes of irrigation and drainage exist to temper the lack, or glut, of water in the soil. However, these practices must be managed carefully if a farmer wants to avoid a saturated harvest. Corn is thirstiest during the hottest summer months of July and August. If roots are shallow due to soil conditions, water is best supplemented in limited amounts on a frequent basis. Otherwise, the soil and corn may get drenched. In a similar manner, the corn may become overly-moist due to decaying or malfunctioning drainage tiling.