Agricultural nutrient application using real-time spectroscopic analysis of live crop

An agricultural nutrient applicator includes a container and a nutrient distribution assembly operably coupled to the container to deliver a nutrient from the container. A spectroscopic reflectance crop sense system is provided that includes an optical window. A presentation assembly is mounted to the agricultural nutrient applicator and is configured to position live plants in a field proximate the optical window of the spectroscopic reflectance crop sense system as the agricultural nutrient applicator moves. A controller is coupled to the spectroscopic reflectance crop sense system and the nutrient distribution assembly. The controller is configured to obtain, from the spectroscopic reflectance crop sense system, information indicative of a measured nutrient level in the live plants and determine a remedial nutrient amount based on the measured nutrient level and a target nutrient level. The controller controls the nutrient distribution assembly based on the remedial amount.