Hello,

If the sumac is sprouting in a lawn, most broadleaf herbicides labeled for use on lawns could be used to control the sprouts. The active ingredient triclopyr is often recommended for use on sumac. Be sure to read and follow the herbicide label directions.

For any sumac growing in landscape beds, spot treating with glyphosate would help in their control. Be sure to protect desirable plants from overspray. 

It would also be helpful to confirm it is a species of sumac. There are similar-looking woody plants that can sprout aggressively from a root system, such as tree of heaven (Ailanthus altissima). It is also important to note that with sumac or tree of heaven, these are likely sprouting from the root system of a larger plant. Both triclopyr and glyphosate will translocate into the roots. If you do not want to kill or stunt the larger plant, a different approach may be needed.