Effect of Douglas fir apparency on the mean damage by C. pseudotsugae. Apparency is the mean height difference between a focal Douglas fir and its direct neighbours. Dots at the right and at the left of the vertical dashed line are Douglas fir trees that are taller and smaller than their neighbours, respectively. Solid and dashed lines represent prediction and adjusted standard error of model 1, with values of other model parameters set at average (Table 1).