Genetic and environmental variation in alfalfa stand persistence from variety testing experiments conducted in North America between 1986 and 1999

<p>The dataset contains stand persistence data from alfalfa variety tests conducted by University researchers in the US and Canada from 1986 through 1999. All trails measured forage yield, and some trials also measured forage quality; these data are also available in PURR. The data are aggregated from the Alfalfa Variety Performance Database originally compiled in 2000 by Daniel W. Wiersma and Wayne G. Hartman (doi: <a href="https://doi.org/10.4231/PHKH-4334" rel="external" target="_blank">10.4231/PHKH-4334)</a>. This database was used to analyze long-term trends in genetic improvement of alfalfa yield and persistence across a broad range of environments</p>

<p>The stand persistence file contains cultivar-specific stand data reported for some, but not all experiments. Units for stand data are percent of a full stand, as judged by the person conducting the experiment. Variation in this subjective judgment over time and space may be present in the data. Stand estimates were generally measured near the end of the experiment. Data are organized by variety and include trial-specific spatial (state, latitude, longitude, elevation), and temporal (year of trial, harvest number, harvest date, planting date) details. Finally, when available soil type and experimental design are also provided. A companion dataset contains the characteristics of these alfalfa varieties (doi: <a href="https://doi.org/10.4231/FMY9-6966" target="_blank">10.4231/FMY9-6966)</a>.</p>