Effects of environmental characteristics upon plant height.

Effects of individual predictors (major columns) were assessed separately for intact plants, injured plants, and for the difference between injured and intact plants (as an interaction). For the intact and injured plants, the response of plant height to increasing values of a predictor is presented graphically using up and down arrows, with the symbol indicating a significant interaction term further characterized in the text. The test statistic is a likelihood ratio to be compared with a χ2 distribution with two degrees of freedom. Type I error estimate (significance) is shown in parentheses for values below 0.1, with others shown as NS.