The external presence of running water influences the root growth of pea plants (Phaselous vulgaris)
(1) Interlake Senior High School, Bellevue, Washington
Each year, invasive tree roots cause large amounts of damage to underground pipes. While this is usually due to leaks and cracks, tree roots can also invade pipes that are structurally sound. We are interested in investigating whether plant roots have an affinity towards flowing water, measured through mass, even when the running water is not in direct contact with soil. We tested this by creating a choice chamber with water running under one end and no stimulus on the other end. We grew the plants in their chambers until their stems reached 10 inches before removing the plants to measure the mass of the roots growing towards either side of the choice chamber. Data from other scientists as well as a previously conducted experiment seemed to show that flowing water attracted plant roots. Therefore, we hypothesized that there would be greater root mass on the side of the chamber exposed to flowing water. Overall, the masses of the roots growing towards flowing water were greater than the masses of the roots growing towards the end with no stimulus, showing that plant roots did have an affinity towards flowing water. The remarkable sensitivities of plants to sound are still being discovered, but the delicacy already shown by experiments such as ours leaves concerns regarding a new facet of the impact of sound pollution on our ecosystems.