In a study on maize and soybean grown together, different ways of separating their roots and shoots were tested to see how they compete for resources. Results showed that when roots and shoots were not separated, soil moisture decreased, affecting maize and soybean growth differently. Maize growth was delayed and biomass decreased, while soybean growth improved. The interaction between above-ground and below-ground parts of the plants influenced their growth and yield, with below-ground parts playing a crucial role.