Natural Preserves demonstrate Iowa's outstanding biological features. Some are excellent examples of the prairies and forests that once dominated the state. Others hold plants and animals now rare in Iowa. Dry bluff tops in the Turin Loess Hills form one of the few suitable habitats for one of Iowa's endangered species, the plains pocket mouse. This preserve also marks the northern terminus of many plants typical of the Ozark Plateau.
Geological Preserves illustrate Iowa's ancient past.
Distinctive and rare deposits or features are included. For example, at Gitchie Manitou, Sioux quartzite 1.2 billion years old protrudes from the earth. These are the oldest outcrops in Iowa. Another geological preserve, the Old State Quarry Preserve, was mined in the 1840's for limestone used in the construction of our original state capitol in Iowa City. Later, blocks of this unusually hard limestone were transported to Des Moines for the foundation of our present-day capitol.