Calibration of five rising plate meters in the Netherlands

Bijeenkomst: EGF2015
Auteur: Holshof G., Stienezen M.W.J. and Galama P.G.
ISBN: 978-9090-289-61-8
Jaar van uitgifte: 2015
Producttype: Paper
To obtain good grassland management, especially under grazing, requires accurate information about grass growth. In the Netherlands several methods have been introduced to estimate herbage mass. At present the rising plate meter is the most accessible tool for Dutch farmers; it is cheap and easy to use. However, the equations for translation of grass height, as measured with the rising plate meters, into measures of herbage mass, have been developed in the countries of origin of the meters. To check the equations for the situation in the Netherlands in 2014 five rising plate meters were calibrated. Grass height was estimated with the five rising plate meters on small plots on which the grass was then cut and dried to measure the dry matter (DM) yield. For each rising plate meter a calibration curve was estimated. DM yield was estimated from ground level and from 5 cm stubble. Information about the herbage mass in the stubble was also estimated by cutting the stubble to ground level. The results show that for three rising plate meters the same equation can be used. Two rising plate meters need a different equation. The rising plate meters are relatively reliable for a measured grass sward of 20-25 cm in height from ground level. This means that a good estimate of DM yield can be made for up to 2,500 kg DM ha‑1 above 5-cm stubble height.