They are called "the life tree" because it is said that life would not have been able to exist here without this precious tree. When the pods dry they are ground into a flour ( a flour that is gluten free and helps control blood sugar levels) . Here is another use I found on http://www.texasbeyondhistory.net/st-plains/nature/images/mesquite.html "The nitrogen-fixing attributes of mesquite may have been recognized by the Pima Indians, who purposely left mesquite trees in the middle of fields as well as leaving them on fence rows, not only because the pods were a good food resource, but also because the falling leaves returned much-needed nitrogen to the soil (Rea 1979)." Desert Harvesters offers grinding events every fall, where they will grind your pods into flour for you. I have a Mesquite in my yard already, they sprout up every where and are hard to kill. I now see that as a plus. Mesquite pods are ripe right before Monsoon, my plan is to collect pods and spread them where I want my trees to grow. I hope this works.
Another awesome thing about mesquite pods is that goats can have them as a snack and so can the kids. I have heard that people make Mesquite Jelly...hmmm that sounds like it's right up my alley.