Publication Date
1989
Description
Extension advisors and farmers in the USA have not usually attempted to quantify herbage mass when making grazing management decisions. Pasture height has been the primary way to decide when to start and when to stop grazing a paddock. Pasture height provides farmers with a simple basis for grazing management with a basis for grazing which considers regrowth rate and quality. However, it is not satisfactory when attempting to « budget » the feed supply or calculate intake. The most accurate method of estimating herbage mass is to cut, weigh and dry samples. Quadrat sampling of the pasture is a method of estimating herbage mass without harvesting the entire pasture. This is laborious, requires large sample numbers for an accurate estimate, and is neither practical nor appealing to farmers and advisors. There are several methods available that allow the estimation of forage yield with a minimum of cut samples used to calibrate various instruments. The electronic capacitance meter (Neal and Neal, 1973; Vickery and Nicol, 1982) weighed disk (Phillips and Clarke, 1971; Vartha and Matches, 1977), visual estimation (Campbell and Arnold, 1973) and height have been used to predict yields without extensive sampling. In the USA these methods have been used primarily by researchers. Recently, economic incentives and renewed interest in grazing management has made it conducive to train extension advisors in estimating pasture mass and budgeting pasture feed supplies. The objective of this research was to develop calibration data for the falling disk meter on mown plots and sheep grazed pastures and to determine if this instrument could be used to train extension advisors in the estimation of herbage mass.
Citation
Green, J T. Jr; Mueller, J P.; and Rahmes, J N., "Using a Falling Disk Meter for Practical Estimates of Herbage Mass" (2025). IGC Proceedings (1989-2023). 35.
https://uknowledge.uky.edu/igc/1989/session12/35
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Using a Falling Disk Meter for Practical Estimates of Herbage Mass
Extension advisors and farmers in the USA have not usually attempted to quantify herbage mass when making grazing management decisions. Pasture height has been the primary way to decide when to start and when to stop grazing a paddock. Pasture height provides farmers with a simple basis for grazing management with a basis for grazing which considers regrowth rate and quality. However, it is not satisfactory when attempting to « budget » the feed supply or calculate intake. The most accurate method of estimating herbage mass is to cut, weigh and dry samples. Quadrat sampling of the pasture is a method of estimating herbage mass without harvesting the entire pasture. This is laborious, requires large sample numbers for an accurate estimate, and is neither practical nor appealing to farmers and advisors. There are several methods available that allow the estimation of forage yield with a minimum of cut samples used to calibrate various instruments. The electronic capacitance meter (Neal and Neal, 1973; Vickery and Nicol, 1982) weighed disk (Phillips and Clarke, 1971; Vartha and Matches, 1977), visual estimation (Campbell and Arnold, 1973) and height have been used to predict yields without extensive sampling. In the USA these methods have been used primarily by researchers. Recently, economic incentives and renewed interest in grazing management has made it conducive to train extension advisors in estimating pasture mass and budgeting pasture feed supplies. The objective of this research was to develop calibration data for the falling disk meter on mown plots and sheep grazed pastures and to determine if this instrument could be used to train extension advisors in the estimation of herbage mass.
