The growing demand for electronic devices in healthcare, environmental remote sensing, and IoT has raised critical concerns about sustainability, e-waste, and the safety of implantable systems. In precision agriculture (PA), achieving dense, real-time field monitoring is still limited by battery-powered nodes that require periodic maintenance and retrieval, by non-biodegradable hardware that accumulates in the soil as e-waste, and by the cost and complexity that cap sensor density and spatial resolution. To address these challenges, a promising direction for modern sensing platforms is to become (a) biodegradable to minimize long-term impact, (b) autonomous via wireless power transfer (WPT) to eliminate toxic rechargeable batteries, and (c) integrated with CMOS technology to ensure efficient energy conversion, robust signal processing, and multi-functionality.