Question

Tree branches  

Spots   Greetings,
Im very worried about my 19 year old Pistache tree. A year and 1/2 ago  I noticed  small smooth white spots on the branches. I scoured the internet and found nothing similar. I live in Dallas and the tree has been very low mantenance. Doing well in TX .Good shade
It had spots but the tree looked beautiful, healthy .  I kind of let it go and didnt think much more about it since the tree seemed to be thriving, UNTIL late spring , early summer of this year,  I noticed  several lifeless branches, small ones ,and everyday I look up at the tree and it seems even more sparce almost 1/4  less leaves. although I think the trunk looks good. This tree means especialy a lot to me and my kids. The spots and seemingly dead branches may be unrelated. I dont  know!!!
Any help you can give would be so greatly apreciated!!!!! I took pics, going to ask someone at  local nursery. But would like to hear what you think.      Thanks Vicki

Answer
The tree looks prretty good (green foliage and looks healthy). The spots are lichens and will not harm the tree. I would begin a fertilizer system. This next Spring ferilize the tree with 10-10-10 fertilizer at the rate of 1 lb of fertilizer per inch of trunk diameter scattered around the tree and watered in good. If you apply the fertiler just before a rian storm you will not need to water. This will increace the overall health of the tree and green the foliage. Apply after leaf out in the spring. Beyind that the tree looks good to me.