FARM VALUE OF TOPSOIL IN SPRING WHEAT PRODUCTION

Relationships among topsoil removal treatments and additions of nitrog en and phosphorus fertilizer on spring wheat yields are used to determ ine the effects on net returns and to estimate the marginal value of s oil. The results indicate that risk-averse managers are not willing to make an expenditure for controlling erosion from the first 2.5 inches of soil if the erosion mte is 20 tons/acre/year or less and the plann ing horizon is 20 years or less. These managers would be willing to ma ke an erosion control investment for the second 2.5 inches of soil equ ivalent to $4.90 to $5.20/acre from the twenty-first to forty-third ye ar in the planning horizon.