A device and method of thinning grape vine shoots comprises a Normalized Differential Vegetative Index (NDVI) sensor. Further, the device comprises a shoot removal whip assembly configured to remove at least one grape vine shoot per stroke. Further, the device comprises a programmable logic controller (PLC) to control the shoot removal whip assembly, the programmable logic controller comprising a memory unit and a processor. Further, the memory unit stores information regarding optimal shoot height and density parameters, and a set of program modules. The processor contained in the PLC takes readings of shoot height and density via the NDVI sensor, and sends an output to a proportional hydraulic valve. The PLC also takes an input from an adjustable gain potentiometer, which allows the user to increase or decrease the acceptable shoot parameters. Via the signal sent to the proportional hydraulic valve, the PLC controls the shoot removal whip assembly, in order to remove a variable number of shoots. This variab