There's a new technology that measures the differences in color of plant leaves.
The lamp, "can differentiate minute differences in leaf colors - indicators of over- or under-fertilization, crop-nutrient levels and perhaps even disease."
The technolgy: "The N-Checker uses two red-light sources that cut down on sensor and polarizer costs and increase the system speed. The red region of the electromagnetic spectrum is important because it reveals not just total chlorophyll content, but also relative amounts of the various types of chlorophyll molecules."
Red
