2009. A summary of research into the effects of mountain pine beetle related stand mortality on snow accumulation and melt

Extensive mountain pine beetle related forest mortality throughout the Interior of British Columbia raises concern regarding the effects of stand deterioration on snow accumulation and ablation, and spring runoff. Studies quantifying post-pine beetle snow accumulation and ablation rates show that, on average, once 50 % or more of the canopy in mature stands has been lost (defined here as grey attack), snow accumulation is only 13 % lower than that in the open compared to a 25 % reduction in mature green/red attack. Reductions in snow ablation rate were similar, on average, in the green/red and grey attack: 38 % and 31%, respectively. The average snow duration in both attack classes is also similar (3-4 d longer than in the open). Differences in snow accumulation and melt are highly variable between study locations and years, with spatial differences often exceeding those related to stand condition. Development of best management practice guidance for broad geographic areas is dependent upon coordinated research efforts at the same scale, as well as consistency in project design, stand description, survey and data analysis methods