How Cranberry Bogs Work

The Fall Cranberry Harvest

When you see pictures of farmers who seem to be standing in the middle of a floating field of cranberries, do you know exactly what's going on there? Simply put, harvest time has arrived.

The process of harvesting cranberries off the vine used to be labor-intensive and inefficient because the berries were hand-picked. Over the years, more effective methods have been implemented to harvest the cranberries.

Since the cranberry fruit has pockets of air inside of it, someone came up with the brilliant idea to flood the bogs with water to help remove the berries from the vines. The first successful water harvesting was in the 1960s; this is the predominant method of cranberry harvesting used today. Also known as wet harvesting, the dry bogs are flooded with up to 18 inches (45.7 centimeters) of water the night before the harvest. The following day, the farmers use water reels nicknamed egg beaters to dislodge the berries from the vines so they'll float to the water's surface. The farmers then wade through the bog and round up the fruit with large wooden or plastic brooms. This process is called corralling. Once the bobbing berries are gathered together, they're transferred to a loading area where they're lifted by conveyor belts. (Sometimes, a pump truck will suck the berries right off the bog.) The berries are then cleaned before processing. More than 85 percent of the crop is harvested in this manner; however, the use of the water reel to beat the berries off the vines is relatively harsh on the delicate fruit. Therefore, wet harvested cranberries are used mostly for juice drinks, sauces, or as ingredients in other products.

Dry harvesting is the best way for farmers to collect the freshest berries. This method of harvesting is used to supply the fresh fruit market. Growers walk with mechanical rakes trailing them. These rakes have metal prongs that are used to comb the berries off the vines. As the machine propels itself through the bog, the tines skim along the ground under the vines, stripping off the berries, which are then elevated into bags. Afterward, the fruit is taken from the bogs by vehicle (sometimes by helicopter) to protect the vines within the bog. The cranberries are then promptly delivered to receiving stations -- and then to your grocery store produce aisle.