Beginning in the 1940's botanists began to notice unique natural ecosystems found in and around Cedars of Lebanon State Park and Forest. These areas are natural rock gardens called cedar glades. The presence of glades is due to limestone rock coming so close to the surface of the ground that it causes the soil to be thin or absent. What little soil is there builds up along cracks and potholes in the limestone slab. Water and surface temperatures vary so much throughout the year that a harsh, dessert-like, inhospitable habitat is created with its own unique plant community. Nineteen rare and endangered species of plants grow profusely here and no where else in the world.