I planted some SWO in Central Oklahoma and have had great luck with them. They are also used extensively for landscape projects around here including new schools and various other places. We average 30in of rain a yr and they make it and thrive. I always water all of my trees a little for the first yr regardless off drought tolerance. I was spooked of them at first, but figured I could try 25 to see what happened and replace if needed. I have lost 2 and the rest are at the top of a 4ft tube now. Like I said I always water a little on the first yr and that's simply because it usually doesn't rain in July and August. Mine have been in the ground since April and came from the MDC.