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Doherty and Perner (Metalinguistic awareness and theory of mind: just two words for the same thing? Cognitive Development, 13 (1998), 279±305) report that children's understanding of synonyms and false belief is dependent on an understanding of the representational mind. Experiment 1 extends this finding by examining children's understanding of homonyms. Children aged 3 and 4 years were asked to judge whether a puppet correctly selected the second member of a homonym pair. Performance on this task was strongly associated with performance on the false belief task even after chronological and verbal mental age had been accounted for. Experiment 2 incorporated two new tasks: a synonyms task and an adjectives task. Understanding of synonyms and homonyms significantly predicted performance on the false belief task. However, once chronological age was accounted for, only performance on the homonyms task did so. The difficulty experienced on the homonyms task was not due to a reluctance to acknowledge that the puppet can point to a different picture when the the same word label is used twice. Children had no difficulty on the adjectives task when the puppet had to point to a different picture described using the same adjective. The suggestion that the understanding of synonyms, homonyms and false belief are related by a common insight into the representational mind is therefore not supported.

The western spruce budworm (WSB; Choristoneura freemani Razowski) shapes Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forests throughout western North America with periodic, severe landscape-level defoliation events. The largest and most continuous recorded defoliation occurred in the 2000s, largely centered in the Williams Lake and 100 Mile House WSB outbreak regions, peaking in 2007 at 847 000 ha defoliated in British Columbia (B.C.). Unique WSB outbreak regions in south-central B.C. are described using biogeoclimatic ecosystem classification, geography, 106 years of documented defoliation, and 46 stand-level Douglas-fir host tree-ring chronologies. Since the 1980s, recorded defoliation in B.C. has shifted from coastal ecosystems and become a dominant disturbance in drier, colder, interior Douglas-fir ecosystems. Defoliation records demarcate four outbreaks from 1950–2012 and up to three growth suppression events from 1937–2012. Outbreak duration was shorter in the north and far south of B.C., with recovery periods (no trees showing growth suppression) shorter over all WSB outbreak regions in the 2000s, suggesting that trees may be increasingly susceptible to each successive defoliation event. Knowing the regional outbreak periodicity may facilitate early detection of incipient WSB populations, which is critical for management as many of our low-elevation Douglas-fir forests become more stressed with changing and unpredictable climate regimes.

This study describes the impacts of 25 damaging agents recorded on young lodgepole pine trees over a 30-year period in a study plot in southern British Columbia. During the study, density fluctuated due to infill and mortality. Of the 1,295 stems per hectare present at the outset of the study, 37% of lodgepole pine died and only 24% of the trees remained pest-free by the final assessment. Pest-free trees were predominantly small and suppressed infill, leaving just over 1,000 stems per hectare of crop trees. Lodgepole pine terminal weevil affected over 38% of pine, with up to six attacks per tree. Fifty percent of lodgepole pine in the study was infected or killed by one or more hard pine stem rusts, with comandra blister rust and western gall rust being the predominant diseases, affecting 32% and 19% of the pine, respectively. Until age 20, 70% of weevil attacks caused major defects. From age 20–40 years, 50% of attacks caused major defects, often forks or multiple tops (stagheads). Defects were more severe when trees were attacked early in stand development. There was a strong correlation between the number of weevil attacks per tree and tree form, and the number of pests recorded per tree and tree form. Two or more pests per tree caused tree form to shift from good to moderate or poor.