You may be on to something there. If the town is not far, or any civilization, see what they are growing. If the soil will support what homeowners are growing, then your mix of plant and trees that should grow there will increase markedly. If there is a lady's "Garden Club" in town, they will be a very good source of information as they will be both older and wiser with regard to plants, trees, and shrubs that they have been successful with and grown. Seedlings are known for the need for water during their establishment period. Perhaps two or three at a time can be watered from a 55 gallon barrel in the back of the truck. Two months I think during the "rainy season", which for for parts of Texas is never, should help get them started.