Rivk from Augusta County, Va writes
Tenacity is labeled as a pre and post emergent for crabgrass but only as a post emergent for nimblewill. The most effective product to control nimblewill pre-emergently has been removed from the market (MSMA). We have had a lot of folks report that Dimension does a pretty good job pre-emergently but since the product is not technically labeled for nimblewill we cannot legally recommend it for this use.
Answer last updated on: 03/13/2019