In the early days of the Soviet Union, Russian scientist Nicholi Vavilov realised that most of the world’s crops could be traced to a handful of ancient centres of domestication. Or conversely that the great landmasses of Australia and North America had produced respectively macadamia nuts and cranberries and remarkably little else. Vavilov’s pioneering work was recognised in the traditional Stalinist fashion – he died of malnutrition in the gulags in 1942. Even today the All-American cranberry can hardly claim to be a truly domesticated crop, as its single most important variety was found growing wild in a bog in the 1840s. In contrast, its cultivation is possibly the most high-tech and strangest of any crop on earth.
The cranberry is a low growing member of the heather family which is native to the acid peat bogs of the eastern USA and Canada. It has a close relative with twice as many chromosomes which is also called the cranberry, but which occurs in similar habitats in both Europe and North America. This European cranberry fruits only reluctantly and produces small paler berries. In parts of Scotland yet another member of the clan, the cowberry is also known as the cranberry and has been harvested from the wild.
Long before the arrival of the Pilgrim Fathers at Plymouth Rock in 1620, the Native American Wampanoags and Narragansetts were gathering cranberries from the wild. The fruit which they called saseminneash were pounded with venison and fat to make pemmican, was used in dying and was believed to draw the toxins from the wounds caused by poison arrows – an invaluable piece of information for those family arguments over Christmas dinner that get out of hand. The European settlers quickly gained a liking for this new fruit and within 43 years ‘The Pilgrims Cook Book’ was describing how to make the perfect cranberry sauce, years before it became a trendy health food. At the time the berries were entirely picked from the wild. With atypical foresight for the time, the Colonists and the Native peoples both recognised the dangers of over harvesting. By 1670 land had been designated for the conservation of cranberries and laws regulated exactly who was allowed to exploit these public bogs. Subsequent laws forbade the picking of unripe fruit and by the 1800’s many areas restricted picking to local residents.
The cranberry finally became an actively cultivated crop as the result of a chance observation made in 1816 by Captain Henry Hall, a veteran of the American War of Independence. The Captain noticed that when he inadvertently showered wild plants in a layer of sand they grew better and produced more fruit, furthermore, transplanted ‘vines’ which he had moved to his own farm responded in the same way. The Cahoon Family, who were pre-eminent amongst early cranberry growers, built upon this development. In 1845 Captain Alvin Cahoon built the first artificial cranberry bog which involved digging a canal to regulate the water supply. In 1847 Alvin’s cousin Captain Cyrus Cahoon constructed the first level-floored cranberry bogs, some of which are still in production. Not to be outdone, Cyrus’s wife, Lettice Cahoon discovered ‘Early Black’ the most important cranberry variety to this day.
Modern cranberry bogs are constructed by stripping the surface vegetation to produce a level peat base. This is then covered in a layer of sand. Laser technology is used to ensure that the bog surface is absolutely level. Ditches and ponds are built to provide the water which is an essential part of cranberry growing. To supply sufficient water for each acre of planted bog, cranberry farmers maintain a further four acres in a complex system of managed wetlands. New bogs are planted with cuttings which take about four or five years to become productive. Each winter, between December and March, the bogs are deliberately flooded to protect the plants from frost damage. They pass the winter snug and warm below their blanket of ice. In spring a system of water sprinklers are used to spray the plants whenever a late frost is predicted.
Until the end of World War I most cranberries were still picked by hand in spite of the fact that the first ride-on harvester was invented in 1920. Today some fruits are still dry harvested by these lawnmower like machines. However, the majority of the crop is destined for processing, and since the 1960’s these berries have been harvested in a most unique way. The bogs are again flooded with about 30 cm of water. The fruits are then stripped from the plants by water reels which thrash them like massive eggbeaters, then because the berries contain pockets of air, they pop to the water’s surface. The bobbing berries are then corralled by floating booms or are blown towards the banks and pumped from the bog. The finest quality, dry, harvested fruits are carefully graded by bounce testing. Soggy soft berries just don’t bounce. Although this test is very simple, it is probably not something that you will want to try while purchasing a tub of cranberries from your local greengrocer.