I know, I know, I’m very late. But has anyone thought about installing a swale to ensure more trees have a chance to thrive? Just asking.
Digging moon mounds is a great way to conserve water as well. Hügelcultures store lots of moisture.
I’m thinking more in terms of enhancing your land.
In terms of variety… maybe plant pigeon peas next to each tree to improve the soil. And it sounds like aloe Vera, prickly pear and dragon fruit would have a blast in your region.
Dates, jujube, pomegranate.. they all love the heat. As for hardy pioneer species, choose the ones that grow in your area for shade and soil improvement.
Within the 15 years of your post and my reply I guess you’ve come to a similar conclusion.
But for all who are still looking for answers, this might be the solution.
Happy Planung and good luck!