Critical Zone Mural (IMAGE) American Society of Agronomy Caption This mural, "Growth," illustrates the reach of the critical zone, from tree tops to underground. The critical zone consists of the plants and animals on the Earth's surface as well as the soil, water, and rock beneath it. Research that takes a critical zone approach looks at how these sections interact. Credit Photo courtesy of the Laramie Mural Project (bhp imaging photo). Usage Restrictions Please use with story only. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.