Reliability of Score-Card Judging of Hay1,2

Abstract

Summary A total of 129 samples of alfalfa or alfalfa-brome mixtures (55 first-crop, 65 later-crop, and nine additional samples) were each scored twice by seven judges, using a score-card based on stage of growth, leafiness, and color and condition. Cutting dates were recorded for the first-crop samples. These dates provided a means, other than the judges’ estimates, of scoring stage of growth on the first-crop samples. Repeatability in the use of the score-card was studied on a within-judge basis by computing the appropriate intraclass correlation. These repeatability estimates ranged from .42 to .80. Between-judge repeatabilities were estimated by averaging simple between-judge correlations. These repeatability estimates ranged from .38 to .78. All estimates of repeatability were highly significant. Simple correlation and multiple regression techniques were used to study the relationship of the score-card and its components to various indicators of nutritive value. Simple correlations were averaged for the seven judges over both scorings. These analyses indicated that the score-card was most effective in reflecting nutritive value when used among later crop samples low in grass content. Among these samples the average correlations between final score and crude protein, crude fiber, estimated TDN, and percentage of cellulose were .50, −.43, .43, and −.51, respectively, and were highly significant. However, among first-crop samples and among later-crop samples which were high in grass content nonsignificant correlations were obtained. The multiple regression analyses indicated that dates of cutting for first-crop samples and leafiness scores for later-crop samples were the most useful criteria of the score-card for predicting nutritive value. However, even among the later-crop samples, where the score card appeared most effective, it accounted for only 20–30% of the variation in estimated TDN.