The pilot reported that as the balloon descended to land, about 50 feet above ground level, a wind gust and down draft resulted in a rapid descent and subsequent collision with trees. The balloon landed hard and bounced several times. During the accident sequence, the basket flipped onto its side and was dragged in the dirt, which resulted in substantial damage to the structure. The pilot reported no preimpact mechanical failures or malfunctions with the balloon that would have precluded normal operation.