Learning how to build a root cellar will help your family preserve food and store food during the winter season. Not long ago, just about every family in the world's colder climes had one of these harvest keepers for food storage - a root cellar. Nestled in the earth-and away from the heat of the kitchen, a root cellar maintained a tempera ture just above freezing and provided practical food storage for root crops, apples, meats and cabbages . . . throughout a long winter.