Also of particular interest for Model I results is the prevalence of statistical significance of
relative prices for both infield and perimeter-field structural practice equations for program non-
participants, while for program participants, this stronger significance effect appears only in the
perimeter-field structural equation. These results would seem to suggest that program non-
participants (for corn farms in the study area) tend to respond to a rising relative input-price
environment with adjustments in the adoption of both infield and perimeter-field conservation
structural practices (attributable to productivity/profitability and field-level cost or scale effects),
while a response by program participants emphasizes adjustments in the adoption of perimeter-field
structures (primarily attributable to field-level scale effects). Non-participant corn producers likely
do give significant recognition to the productivity/profitability benefits of infield structural practices
as sufficient to encourage their adoption without program incentives (these practices account for
nearly 70 percent of their conservation structural acres). On the other hand, all producers also likely
recognize that the primary benefits of perimeter-field practices are off-site, but that program
participants adopting these practices tend to require a program incentive to encourage their
adoption, particularly in response to the field-level cost (scale) effect associated with a rising energy
price environment.
Additionally, coefficients for the technology class variables (i.e., corn field acres with only
infield structural practices, only perimeter-field structures, or with both infield and perimeter
structures) were not highly statistically significant. Only the technology class variable for the
presence of both infield and perimeter-field structures was significant at the 15 percent level. These
coefficients reflect the relative effect on corn field acres for the adoption of a structural conservation
practice associated with the respective structural (technology) class. The results indicate that
producer relative responsiveness to reducing corn field acres is greatest when adopting both types of
conservation structures, and lowest when adopting only infield structures.
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