I made a trip to the woodstore yesterday, they had some 12/4 Poplar in stock at a fair price for the desert so it will be the base wood. I also picked up a small piece of 8/4 Poplar for the short cross stretchers.
I rough cut the 8/4 short stretchers yesterday. The 12/4 stock is marked for rough cutting to size for the legs and long stretchers. The woodstore was short on 8/4 Beech for the slab, it will require a return trip.
A photo of the Poplar, even Poplar is a heavy sucker once it gets 12/4 thick.
Here is last year's bench: