Prediction of corn grain yield and management of nutrients by-plant have recently been a focus for major research. This study was conducted to develop a sensor capable to locate plants in a field and to electronically measure corn plant diameter. Data was collected during summer 2011 in Oklahoma, and spring 2012 in Obregon, Mexico. Photoelectric sensors and optical encoders were mounted on a push cart to measure plants electronically. The output data was analyzed using an algorithm developed to obtain plants location. Results for 2011 showed that location prediction was high as 82% for V8, but, in contrast, for VT is dropped as lowed as 40% due to leaves or other objects detected by the sensor. The absolute error was below 5 cm. The 2012 study showed similar result.
