Anyone growing Rhus copallina var. latifolia 'Morton'?

I have a hillside of white pines with an adjacent 30' x 30' grass opening. I have an assortment of native shrubs on the other side of the opening. The grass on this hillside is now dead thanks to the drought and the hot location. I'm considering replacing the dead sod with 'Prairie Flame' Shining Sumac. I want it to look somewhat naturalized and massed, with the added benefit of not having to mow the hillside.

Does 'Prairie Flame' sumac behave itself so that mowing where I want to keep it within bounds will be all that's required. And secondly, will I need to grow something under this plant to prevent erosion and suppress weeds. If so, what would you recommend. Finally, can I plant this species in the fall or should I wait until spring?

Just so you know where I'm coming from, I mostly do native plants in my yard, but I'm not opposed to adding a few non-natives to increase design possibilities especially when it comes to lower maintenance and function, so please advise accordingly.