An agricultural planting machine is described. In one example, the machine comprises a trench opener configured to open a trench, and a trench depth sensing system comprising a ground-engaging component and a trench depth sensor configured to generate a signal indicative a displacement of the ground-engaging component by directly sensing a surface of the ground engaging component. In one example, an agricultural planting machine comprising a trench opener configured to open a trench, and a trench depth sensing system comprising a ground-engaging component and a capacitive sensor comprising a transmitter element driven by an input signal to generate an electric field and a receiver element configured to generate an output signal based on a capacitive coupling between the transmitter and receiver elements, wherein the capacitive coupling changes based on movement of the ground-engaging component within the electric field. A trench depth calculation component is configured to generate an indication of trench depth based on the output signal.
