Ongoing farmland loss has led county planners to ask “is there a critical mass of farmland needed?” to retain a viable agricultural sector. This study examines whether counties lost farmland at a faster rate if the number of agricultural acres fell below a critical threshold. Results from six Mid-Atlantic states over the period 1949 to 1997 indicate that counties with fewer agricultural acres lost farmland at a faster rate. However, after splitting the study period into two time segments (1949–1978 and 1978–1997) and modeling separately, this result was not found for the later time period, suggesting a uniform critical mass level may not exist. Population growth in a county accelerated farmland loss over all time periods.

Data on owner and land characteristics are used to analyze factors affecting participation decisions in Delaware's agricultural lands preservation program, federal commodity programs, and federal conservation programs. A trivariate probit model estimates a set of random utility models of participation. Participation decisions at the state and federal levels are found to be driven by many of the same observed factors, but uncorrelated in unobserved characteristics. The important exceptions are that owners of small parcels under development pressure and with parcels of relatively low environmental quality tend to enroll in commodity programs rather than preservation. In part, the complex policy environment may therefore limit the effectiveness of programs seeking to preserve parcels with the highest environmental quality or facing the greatest development pressure.

Florida's open-space land-acquisition program is one of most aggressive in the country, with $3.7 billion paid for 3.8 million acres since 1972. Using data from the Conservation and Recreational Lands (CARL) program, hedonic analyses found that acquiring private lands with valuable natural resources, habitat for rare species, and important historical sites for public preservation is more costly. Development potential and pressure also increased acquisition costs. The presence of additional endangered natural elements and needing to contract with additional landowners, however, were found to decrease the cost. Results provide a basis for landowners and land-acquisition agencies to negotiate.