I planted a peach seed about 5 years ago. Currently it is planted in clay soil. Some of the leaves are yellow, and some of the branches just look dead. I have some links to pictures of it. Does it look diseased? Is it dying? Should I prune the dead looking branches? Why isn't it growing? What can I do to help it grow more? Should I aerate the soil? http://s751.photobucket.com/albums/xx154/testaccount_2010_photo/Peach%20Tree/
The number and placement of the yellow leaves on the tree looks completely normal. Most of the leaves look quite healthy. It's not uncommon for a few yellow leaves to appear, especially if some dieback is occuring on the tree. It appears the the dieback on your tree is at the branch tips. This could be due to extremes in environmental conditions (such as extreme heat and drying). The blackening of the stems could also be an indication of canker (a fungal disease). Fungal diseases are usually less severe in a dry climate such as yours, but you may need to spray preventative fungicides to protect your peach tree from diseases.