pressing of beds, and application of plastic mulch. To prevent escaping fumes of fumigant, the

edges of the plastic are covered with soil to seal the edges (Hochmuth, 1988a). Fifth, water is

maintained approximately fifteen to eighteen inches below the soil surface to ensure seepage into

the root zone and to maintain moisture. By maintaining a moist environment, a nutritional

concentration gradient exists. This allows the banded nitrogen (N) and potassium (K) to diffuse

into the soil and replace those nutrients already incorporated into the soil. Plastic is extremely

important in maintaining soil moisture, otherwise the nutrients can be lost to leaching by natural

rain, or the soil may dry out and result in evaporative loss of soil moisture (Geraldson, No

Date).

 Mulched tomato production with overhead irrigation is similar to a full-bed mulch system

 with seep irrigation with the following exceptions. In sandy soils all fertilizers are incorporated

 into the soil. In areas with a soluble salt problem, a percentage of fertilizer is incorporated into

 the soil and any remaining fertilizer is added as required. Perforated plastic is not required,

 since the water that is applied, soaks in at the hole in the plastic and is sufficient to supply plant

 needs. Some methods of overhead irrigation include the use of travelling guns, solid set

 sprinklers, or center pivot systems. One disadvantage of overhead irrigation is the threat of the

 spread of foliar diseases due to increased moisture on the leaves. In rockdale soils perforated

 plastics are required due to minimal lateral water movement in the soil. Placement of

 superphosphate close to the transplant is also required for uptake because phosphate is considered

 immobile in the soil.

 A mulched tomato production system with drip irrigation is similar to a full-bed mulch

 system with seep irrigation with the exception of the following. Drip irrigation is accomplished