Image is here:http://forums2.gardenweb.com/forums/load/trees/gal1116391828630.html The soil is fairly rocky, verging on caliche. When I planted the tree I dug the hole twice the width and same depth of the pot it was in. I filled it with water and it drained in a little more than an hour. I mixed the original soil with Miracle Grow garden soil at about 50-50. When I try and test the soil for moisture, it usually results in me hitting a rock with my test rod at about a foot deep. I've stopped watering for about 5 days now and the tree looks the same. I haven't tested the soil since I've stopped watering but I'm guessing my test rod will not get through much. I think I should have amended the soil with some sand and compost to improve drainage.

I just lost the very same tree. I live in Arizona and ours didn't bloom this year so we checked it out. Same issues as yours, we lost all the leaves and the ends of branches were turning brown. Then we noticed that the usually green trunks were turning gray. It was a boring type bug. It is coming down now off it's own, because it looks to be dead. We did ask around to experts, there is no help for it. So sorry. I was so sad to lose my tree, it's so pretty in spring with all the flowers. Ours was well over 12 years old. I wish I could give you some advice to save it, but we were told there is nothing to help.

They are actually easy to kill, because they don't sprout well from the roots. Cut the tree down and IMMEDIATELY swab the entire cut surface with generic glyphosate (Walmart's "Eliminate" brand is widely available and cheap). If it sprouts a bit, clip or pull the sprouts off as you see them. The seedlings ... just keep pulling them as you see them and eventually you get them all.

The nursery would be great (Walter Andersen in Pt Loma very helpful for me and where I bought several of these trees). Would help to know what type palo verde tree. You could also try contacting AZ Plant Lady Noelle Johnson (who I discovered here on Houzz!) She's an expert in desert type plants and has many interesting articles such as this one: [10 essential native trees for Southwestern gardens.[(https://www.houzz.com/magazine/10-essential-native-trees-for-southwestern-gardens-stsetivw-vs~72712112) Lgteacher, great point about establishment..... and that's the first time someone ever suggested a person follow my plant advice LOL! Thank you :) I struggle so much in the garden. There are many knowledgeable folks on this forum so hopefully someone can chime in if and how you can help your tree Henry Ho!