c. 1852: Baltimore & Ohio Railroad Reaches Ohio River. Expanded the oyster market to western communities; northern oyster packers opened plants in Baltimore.

1865: General License System; Five-Acre Law. State-wide license system regulated oystermen; leasing law allowed oyster planting on five-acre plots.

1868: "Oyster Police." Collected license fees, enforced fishing restrictions, and protected private grounds.

1877-79: Winslow Oyster Survey. Documented expansion of oyster beds and decline in number of oysters in Pocomoke and Tangier Sounds.

1882: Oyster Commission. Surveyed Maryland oyster beds; recommended conservation measures and oyster farming.

1890: Cull Law. Set minimum legal size for market oysters; required return of shells with spat and young oysters to natural oyster bars.

1906: Haman Oyster Culture Law; Shellfish Commission. Increased leasing allowance, a proposal rendered ineffectual by later legislation; commissioned Maryland Oyster Survey (Yates Survey).

1906-12: Yates Survey of Natural Oyster Bars. Conducted extensive biological and environmental surveys of Maryland's oyster bars.

1916: Maryland Conservation Commission. Consolidated Shell Fish Commission, Fish Commissioners, State Game Warden, and State Fishery Force (Oyster Police) into one agency.

1922: Shell-Planting Legislation. Initiated annual placement of shell as cultch for depleted oyster bars.

1927: Ten-Percent Shell Tax. Required oyster processors to make 10 percent of their shucked shell available for state use in planting.

1947: Twenty-Percent Shell Tax. Increased shell tax on processors.

1953: Fifty-Percent Shell Tax. Increased shell tax again, but the supply still proved insufficient.

1961: Shell-Dredging Program. Initiated new oyster repletion program using old shells dredged from non-producing areas

1965: Twenty-Five Percent Shell Tax. Reduced shell tax; allowed processors the option of cash payment, in place of shell. 1972: Moratorium on New Leases. Suspended awards of new leases of oyster grounds pending completion of new survey of state oyster grounds.