Most trees can withstand a few days of flooding during the growing season. Since the effects of flooding on trees involves a complex interaction between flood characteristics, soils, and individual tree tolerances, predictions of tree survival from flood conditions are difficult to make. The complexity of the interactions has resulted in contradictory information from different studies about tree response to flooding, but some generalizations can be considered. Damage is usually greater on trees where the foliage is submerged and tends to increase as more foliage is covered with water. Impact from these chemicals depends on the concentration and type of chemical.
Flooding can modify soil characteristics in many ways.
Flooding can cause anaerobic conditions. A lack of oxygen can cause poor root growth and eventual death of a tree can occur after extended flooding. Hydrogen sulfide and ethanol can damage roots as it builds up through anaerobic decomposition. Tree health, size, age, and species can all affect the ability of an individual tree to survive flooding. Vigorous trees tend to be damaged less by floods than stressed trees.