Oysters have been a favorite food since ancient times. They were cultivated in China before the Christian era. The Greeks and Romans enjoyed them; also the Indians in America long before the white man came. We know, they keep well if treated properly. After Caesar's conquest of Britain, oysters found there, by the Roman soldiers, were transported to Italy in bags, packed in snow and ice, to grace Roman banquet tables. Today, aided by modern refrigeration techniques and transportation by air, oysters are shipped long distances from the various growing areas and enjoyed throughout the world.
There are more than seventy edible species of oysters, but only a few of these are grown commercially. Along the Pacific Coast, from California to British Columbia, the Pacific or Japanese oyster dominates. Pacific oysters are larger than the Eastern or European oysters with a rich, succulent flavor. Young oysters are excellent raw on the half shell; larger oysters are tasty in stews and other cooked dishes.
The myth that oysters are only good through the 'R' months is no longer true. Modern cooling and shipping systems lets you enjoy the oyster year-round, though their taste may vary in saltiness, depending on the amount of fresh river water that makes its way into the estuaries and inlets where oysters grow. Some connoisseurs go as far as saying, they can tell where an oyster was grown by its flavor, probably due to the variation in mineral composition of the soil in the different bays.
The other myth that oysters are an aphrodisiac may be due to their excellent nutrient content, especially vitamin E and zinc. Newer methods of nutritional analysis have shown the oyster to be very low in cholesterol. The "fat" is not fat, but glycogen, and animal starch. Normally glycogen is highest from October to June. Oysters are a source of protein, several vitamins, sodium iron, potassium, calcium, magnesium, iodine and phosphorus and 16 or more trace elements.
In some warmer inland bays, the oyster may spawn in July and August; the meat may turn milky, but oysters are edible, however they might look better in cooked dishes.
Oregon oyster growers either set their own seed in temperature controlled tanks, in which case they buy the oyster larvae. Or they buy their seed by the truck load from Washington State where the seed may have been set naturally in the water where the oysters spawn. In most Oregon bays, maturity to market size requires two and a half to four years.