Snow avalanches break, uproot and overturn trees, causing damage to forests. In this paper, we define avalanche loading cases representing four different avalanche flow regimes: powder, intermittent, dry and wet. Using a numerical model that simulates both powder and wet snow avalanches, we study documented events with forest damage. We find that powder clouds with velocities over 20m/s break tree stems and that quasi-static pressures of wet snow avalanches are much higher than dynamic pressure.