Dying apple tree
My limbs are dying, one by one. I have one tree that died already. Let me know if you need better or closer pics. Thank you. email@example.com
Las Vegas? Water deficit (drought stress) will be your biggest concern. The lawn irrigation may not be enough. You need to establish a large planting bed without grass that competes for water and nutrients. Mulch the soil surface to retain soil moisture. Fertilize and water heavily and deeply at least twice a week in the summer heat. Try to achieve 10 inches of water penetration depth into the soil.
Use dormant spray (horticultural oil and copper) during the winter when the leaves are off. Use neem oil during the spring to suppress pests and disease. Discontinue neem oil spray in early May when temps start hitting 90.
In that climate as you know, water is everything. Enough and plants can do okay, not enough and it's certain decline. If you can't water adequatey for whatever reason, plant a mequite, a palo verde or cacti.