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Invasive species often rapidly spread due to their ability to adapt to a wide range of habitats they can occupy and lack of competition. Hydrilla verticillata is an invasive aquatic macrophyte that has spread across the United States due to human activities. Like many aquatic plants, Hydrilla has the ability to reproduce through fragmentation of the mother plant. In this method, Hydrilla fragments are then dispersed by water current to other areas where they can settle and grow. To date, little is known about the abiotic conditions that may restrict the spread of invasive Hydrilla. However, compared to other macrophytes it is reasonable to believe that water temperature may play a critical role in the success of the plant. To investigate the thermal tolerance of Hydrilla, we plan to grow plant fragments in a controlled laboratory environment. Hydrilla fragments (7 cm) will be weighed and planted in individual containers jar and then maintained in a 76L aquarium kept at 26°C. Each plant will be given a two-week acclimation period to promote rooting before being moved into a growth chamber with a 12hr light and 12hr dark photoperiod for thermal trials. Trials will consist of four temperature treatments (10°C, 20°C, 30°C, and 40°C) with 12 plants per temperature treatment lasting for a duration of 30 days. After the 30-day growth period, each plant will be removed from the growth chamber, weighed, and measured for height. Based on previous work, we suspect that Hydrilla will stop growing at temperatures below 16°C and at temperatures above 30°C. Understanding the thermal tolerance of Hydrilla is critical for predicting establishment success and managing future spread in introduced environments.