The distribution of attack by Scolytus tsugae (Swaine) between and within trees was evaluated in a small, isolated stand of Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) saplings in northern Idaho. Distribution of attacked trees was determined from a complete inventory of the stand Within-tree distribution of attack was evaluated from sample bolts removed from three levels of each of nine sample trees. The infestation was concentrated (> 50%) in the 5-in. (12.7-cm) (dbh) trees during the 3-year outbreak period, but spread to the next smaller and larger diameter classes during the peak year. Approximately 52% of available host trees in each of the 5- and 7-in. (12.7- and 17.8-cm) diameter classes were killed during the outbreak. The lower and middle thirds of the bole sustained the highest number of attacks per ft2 (930 cm2). There was no significant difference in the percentage of successful attacks per ft2 (930 cm2) between tree level; however, the degree of success tended to increase with height in the tree.