It’s not uncommon to see a tree suddenly die during this time of year.
Tree research conducted about 30 years ago showed that at least 50 percent of a tree’s root system would be nonfunctioning or dead before the tree exhibited above ground evidence that it had a problem. This generally means that by the time a person notice the problem it’s too late.
When you see a tree that appears to suddenly die, you are usually dealing with a tree that has had problems for quite some time (sometimes months or even years before the tree’s death).
Homeowners will sometimes call and make a statement such as, “All the leaves on my tree suddenly turned brown but are still hanging on the tree and are firmly attached.” I usually respond by telling the caller that this is an indication of severe root injury. Usually a combination of factors over a long period of time caused extensive root injury. The tree had been functioning with a weakened, smaller root system. The extended hot, dry weather ends up being the “straw that breaks the camel’s back” for these already stressed/weakened trees.
Common causes for lethal root injury in trees include construction damage, floods, drought and herbicide injury (many trees are damaged by “weed and feed” products. Burying tree roots too deep under the soil and mulch is a common cause for the decline/death of young trees. Tree roots must have adequate oxygen. Planting too deep suffocates the roots, possible killing the tree with time. A combination of the above might be at play when a tree appears to suddenly die. Vascular diseases and insects might be involved but they are usually secondary. There usually is nothing that can be done to correct this kind of injury in trees. These types of problems are prevented, not cured.
The initial damage might have been caused years before the tree’s leaves suddenly turn brown. Based on my experience, trees in this category do not recover. I think homeowners want me to tell them that there is a product on the shelf at some garden supply store that will magically result int he tree coming back to life. But the bad news is that by the time a person is aware that a tree is in trouble, it is usually too late to reverse the damage. But knowing this might help you not waste your time and money attempting to cause an already dead tree to live.