Any chance of a picture?

Yes, I wondered too. Not come across a grafted sumac before. Hence the request for a picture.

perhaps we ought to start with location.. add pix ... confirm ID ... then you state your pruning goals .. and then we can opine ...

pruning requires goals.. perhaps other than.. i want to beat it back with a stick .. lol ... which you can do.. without an ID ... if you look inside the plant.. you can probably see how it was pruned previously ... not that that was necessarily a good job ...

ken

Hi again..finally got a photo. This was s on my back patio. I would like to keep it small and a nice round shape. Am I wrong calling this a sumac, it has the red plume type flowers but not many this year. Please ignore my grand daughters fairy house that she hung from a branch.

No, you're right, it is a stagshorn sumac but I see no reason to suppose it's grafted. I actually like the contorted bonsai she look. As Ken says, what are your goals? What do you want it to look like?

Thank you. I just find it is too big for that spot in my yard. Can I prune it so that it does not get so big.

Forgot to add I am in zone 4.

Yes, you can prune lightly it. In my experience, heavy pruning on a Staghorn Sumac will cause it to respond with vigorous growth. The more you cut off the more it will grow back. Vigorous growth on this species could mean 4'+ in a season.

So would this be too much or could I do more.

That'll likely be fine and not trigger a rapid regrowth.