Assessing the ability of a stationary pasture height sensing device to estimate pasture growth and biomass

Abstract

Good pasture management requires an accurate knowledge of whole-farm feedbase, yet most systems for measuring pasture growth are manually operated and time consuming. A newly developed pasture-measuring device enables remote measurement of pasture height on a regular basis. This study investigated the accuracy of such a device compared with a rising plate meter, then assessed the device on a pure perennial ryegrass paddock at a research farm, followed by field testing in a perennial ryegrass/white clover paddock on a commercial dairy farm. A strong correlation (R2 = 0.93) was obtained between collected DM yield and device-derived pasture height within the pure perennial ryegrass paddock but the correlation was weaker (R2 =0.68) with data from the dairy farm perennial ryegrass/white clover paddock. There is considerable potential to improve upon these initial data through the use of adjusted calibrations. Findings demonstrate the device has the potential to accurately estimate pasture growth.