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The burning of nine, one-meter tall chamise shrubs with a maximum shrub diameter of 0.7 m, placed in a 3×3 horizontal array arrangement was simulated using WFDS (Mell et al. 2009). All shrubs were simultaneously ignited from their bases by individual ignition zones located on the ground beneath the shrubs. Several simulations were performed by varying the shrub separation distance from zero to the maximum shrub diameter. The burning characteristics of the shrubs were examined for the conditions of no wind and a wind speed of 1 m/s. For the no wind condition, the peak mass loss rate of the shrub situated at the center of the array was found to be significantly higher than the rest of the shrubs. This finding indicated the heat feedback enhancement to be dominant and thereby caused the center shrub to burn intensely and exhibit fire merging. On the other hand, in the presence of wind, the shrub positioned in the middle of the array edge in the downstream direction exhibited the highest peak mass loss rate. This behavior was attributed to the tilting of flames in the downstream direction influenced by wind and thereby enhancing the heat feedback from the flames of the upstream shrubs. For a separation distance equal to the maximum shrub diameter, the effect of heat feedback was significantly reduced and the shrubs exhibited a burning behavior akin to that of an isolated, single shrub.