Florida has received an exceptional amount of rain this summer that has led to flooding on our rivers, creeks, swamps, and other low lying areas. Although trees require water to grow and stay healthy, too much of a good thing can stress our trees causing growth loss, disease, insect outbreaks and in some cases death.
A few tree species, such as bald cypress, is adapted to frequent flooding and will survive this excessively wet summer without harm. However, many of our trees will be stressed for several years even after the high waters recede. The first symptoms usually noticed are leaf yellowing, shoot growth, crown die-back and defoliation.
There are many factors that determine if a tree will survive flooding including species, age, vigor, flood duration, location, soil characteristics and the time of year. Once a tree becomes weakened, it is more prone to insect and disease damage. When the ground becomes saturated, conditions are ideal for fungal problems that lead to root rot diseases. Flooded soil conditions promote reproduction and dispersal of these fungi but also promote the susceptibility of roots to infection. Saturated soils also reduce soil oxygen levels that may cause some roots to die leaving the tree with a smaller root system to recover from the stress.