Food storage was determined regionally. Most tribes used underground caches or protected shelters. In the Northeast these storage areas may have been as deep as six feet. The sides and bottom of these pits were usually lined, sometimes with stone or bark and often with fragrant, durable grasses. Sometimes the food being stored was paired with compatible vegetation; for example, the Iroquois used sumac leaves with squashes and hemlock branches with corn. Pits were roofed and made watertight and then disguised with coverings of soil or brush. In many ways similar to European root cellars, storage areas after contact were occasionally made of wooden planks and straw. Northern tribes sometimes took advantage of cold and perhaps freezing streams: the Makah submerged alder-bark cones containing elderberry clusters into cold creeks. Indoor granaries served short-term needs. In the Northeast, granaries tended to be large, chestlike constructions of elm or birch bark that may have held sixty bushels of shelled corn. The granaries of the Luiseño held acorns. Outdoor above-ground corn cribs for drying and storing ears of corn were built by the Iroquois.