Mature trees help to keep the river in its channel. In addi- tion, they can lower water temperature by providing shade. The cottonwood is self-pruning. Much of the deadfall and broken limbs remain on the ground making passage through thick bosque difficult and adding to the fire hazard. Bosque vegetation is extremely hardy and resilient when compared to most southwestern vegetation.
Most bosque plants tap the water table and therefore have an almost constant supply of water.