Marked temperature inversions are produced when cold air from surrounding uplands flows into the valley at night. High relative humidity of the bosque adds a chill factor. Four main tree types dominate the bosque. Tamarisk grows particularly well along riverside drains where the root structure of native trees has been disturbed by dredging. More data is necessary to describe the succession pattern for exotics.
Tamarisk appears to have the potential for replacing willow in some areas.
Where cottonwood grows it appears to be the climax species due to its greater height and canopy. Recent strands are mixed with Russian olive. Thick cottonwood bosques are relatively unproductive for most wildlife, although they provide important cover. Disturbed areas, such as old burns which are returning to forest, provide more useful food production. The succession pattern on burned areas varies with the severity of the fire, soil, water conditions, and other fac- tors.