This area was once covered by forests, but over time the rich soil and abundant natural resources of the Ohio Valley drew people who cleared the land for crops and farm animals, and later development added homes, roads, monoculture farming, and industry, drastically changing the landscape. Native species help restore natural balance by replicating part of the lost ecosystem that made Southwest Ohio rich for indigenous peoples and later arrivals. Native plants attract and sustain native pollinators and beneficial insects, and nearly 80% of flowering plants need a pollinator to reproduce. Local insects and plants have evolved and adapted together over many years, and healthy native insect populations in turn feed local birds, fish, and mammals. Suburban gardens can help because native plants use less water, fertilizer, and pesticides than grass lawns and non-native plants, have deep roots that prevent soil erosion, and support native pollinators such as bees, butterflies, moths, bats, and hummingbirds, which are in serious decline. Adding native plants to a yard can increase native insects, the base of the natural food chain, promoting biodiversity and preserving natural heritage. A millstone used to mill grain in the early 1800's was found on the Chrisholm Farm.