Measuring soil light response

摘要

A soil measurement probe is disclosed which includes a housing (30) that defines a force axis (32). The housing has an outer surface (34) that is exposed for sliding contact with soil as the housing is moved through the soil along its force axis. The housing defines an interior cavity (36) therein. A window (38) is mounted in an opening (40) in the outer surface of the probe and provides optical communication between the soil and interior cavity. An illumination means (42) is located within the interior cavity and is directed toward the window (38) for illuminating the soil in situ with multiple light wavelengths in succession. A sense means (44) is located within the interior cavity and is directed toward the window (38). The sense means is responsive to light of each of the first and second wavelengths as reflected from the soil in situ.