Monitoring forage mass and nutritive value of pastures are encouraged to ensure adequate and efficient grazing management. For on‐farm monitoring, reliable instruments such as the rising plate meter (RPM) are useful and easy to achieve. The objective of this research was to verify the relationship between measurements of RPM (MRPM) to forage nutritive value based on seasonal and diurnal changes within a tall fescue sward under continuous stocking management. The study was conducted at the Plateau AgResearch and Education Center in Crossville, TN, from January 2015 to December 2016. The experiment was conducted in two 9‐hectare pastures consisting of a tall fescue [Schedonorus arundinaceus (Schreb.) Dumort., nom. cons., formerly Festuca arundinacea Schreb.] sward. During the 12‐month grazing period each year, total aboveground available forage was measured monthly in each pasture with a calibrated RPM. In addition, each month, several randomly placed 1‐m² sample areas were collected at 7 a.m., 9 a.m., 12 p.m. and 4 p.m. to characterize forage nutritive value. Neutral detergent fiber, crude protein and in vitro total dry matter digestibility (IVTDMD) were predicted by means of near‐infrared spectroscopy. During the entire year of 2015, all correlation coefficients of forage nutritive value variables with MRPM were significant. However, in 2016, only IVTDMD showed a significant correlation with MRPM. Of the nutritive value variables, we chose to focus on the IVTDMD and MRPM relationship because it had one of the highest correlations for most seasons and different times of day, especially in 2015. There was a strong relationship between RPM measurements of herbage mass with IVTDMD, and this relationship is especially useful during the spring, where rapid growth is occurring. The same relationship was not found to be consistent during periods of slow forage growth, especially if recovering from a drought event.

中文翻译：

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连续放养下高羊茅草场牧草营养价值与质量的季节和昼夜关系

鼓励监测牧场的草料质量和营养价值，以确保适当和有效的放牧管理。对于农场监测，可靠的仪器如升板仪 (RPM) 非常有用且易于实现。本研究的目的是验证 RPM (MRPM) 测量值与基于持续放养管理下高羊茅草丛中季节性和昼夜变化的饲料营养值之间的关系。该研究于 2015 年 1 月至 2016 年 12 月在田纳西州克罗斯维尔的高原农业研究和教育中心进行。该实验在两个 9 公顷的牧场上进行，牧场由高羊茅 [Schedonorus arundinaceus (Schreb.) Dumort., nom., nom. cons., 以前的 Festuca arundinacea Schreb.] sward。在每年 12 个月的放牧期间，使用校准的 RPM 每月测量每个牧场的总地上可用草料。此外，每个月，在上午 7 点、上午 9 点、下午 12 点和下午 4 点收集几个随机放置的 1 平方米样本区域，以表征草料营养价值。通过近红外光谱预测中性洗涤纤维、粗蛋白和体外总干物质消化率 (IVTDMD)。2015年全年，牧草营养价值变量与MRPM的相关系数均显着。然而，在 2016 年，只有 IVTDMD 显示出与 MRPM 的显着相关性。在营养价值变量中，我们选择关注 IVTDMD 和 MRPM 的关系，因为它在大多数季节和一天中的不同时间具有最高的相关性之一，尤其是在 2015 年。牧草质量的 RPM 测量值与 IVTDMD 之间存在很强的相关性，这种关系在春季尤其有用，因为春季生长迅速。在牧草生长缓慢期间，发现相同的关系并不一致，尤其是在从干旱事件中恢复时。