Armillaria Root Rot

We have three large linden trees on the north side of the Spring-Green corporate office. Whenever I go to the lunch room, I look out the window and see one of the trees. Earlier this year, I started noticing some mushrooms growing at the base of the tree. I also noticed that the tree was dropping its leaves earlier than normal and the leaves that remained on the tree were curled under and smaller than the leaves on the other two lindens. These three conditions usually mean that the tree is suffering from a disease known as Armillaria Root Rot. When doing some research on the disease, I read that trees under stress from prolonged drought, repeated insect defoliation, root injury or recent transplanting are susceptible to the Armillaria root rot. The linden trees growing at Spring-Green's office are a popular choice for Japanese beetles to feed on, and are often severely damaged by their feeding every year. In regards to drought stress, we have had our fair share of dry weather in the past, even though we have a sprinkler system." These trees have been in place for over 30 years, but they are also being affected by a common root problem often seen on transplanted trees – girdling roots. Root girdling is caused by a root that grows over the top of other roots, often times at the main trunk, which restricts the growth of the tree or root, preventing the movement of water and nutrients throughout the tree. So, the tree in question definitely has root stress. What can be done about this disease? Unfortunately, there is little that can be done to correct this situation. We will do what we can to keep the tree around as long as possible, but I am afraid it is not long for this world. I guess we could call it the circle of life, but it is such a pretty tree and we will be sad to see it die."