We have a large rhododendron that must have been planted many years before we moved into this house in January 2003. In the past year or two it has developed what looks like dieback on some of the branches. Some of the branches I have already cut off; others have died since then. The previous owners (who were here nine years before us) did not do much to look after any of the garden before we moved in: the garden was quite neglected and overgrown before 2003, but the rhodo seemed quite healthy until a year or two ago and has always bloomed profusely every May. In trying to guess what could be causing the problem I have come up with the following possibilities, none of which I am completely sure of: 1. We had the perimeter drainage around the house redone two or three years ago and the digging around the base of the house near where the rhododendron is could have (a) damaged the roots (but the dieback would have to be a very delayed reaction) or (b) changed the drainage pattern in the soil around it. We also had the sewer line replaced, for which there had to be digging right under the rhodo. (But this was about four years ago.) 2. I have watered the rhodo occasionally in the summer, but not as much as other plants. If the drainage around it is poor, the summer watering could have caused a root fungus. 3. The gutters on the house above the rhodo have a concave corner that is very prone to getting filled with leaf drop from large cedars that are near the house. In the winter rain tends to spill off that corner of the roof onto the ground near the rhodo. I had thought, however, that having redone the perimeter drainage, any such water would be taken away into the drainage system. If this is the problem then it is a mystery that it didn't happen with the previous owners who generally did not keep on top of house maintenance. I have posted several photos of the rhodo that attempt to show the dieback. I also posted one photo of a R. siderophyllum that is growing near it. We got the siderophyllum two or three years ago and originally had it growing in a very tough spot under two cedars. I moved it to this spot last November (I think) and as the photo shows, it is blooming very well. Should I be concerned about having the siderophyllum close to the affected large rhodo? Even closer to the affected rhodo is an Olga Mezitt that we planted two or three years ago, which also is very healthy. I would appreciate any advice about or identification of the problem with the affects rhodo.