France have suffered back-to-back defeats in the competition thus far, but Rowntree has refused to accept that Les Bleus will provide easy opposition.
"Philippe Saint-Andre is already saying this is their Grand Slam. It will change the whole complexion of their championship if they win at the weekend and the way they will challenge us is through their forward pack," Rowntree told reporters at a press conference.
"There is never a weak French scrum. We are preparing for Thomas Domingo . I think he will start. We have been watching him play for Clermont. He has been around that set-up for a few years now.
"He is an incredible scrummager, a compact little unit but technically very good. As an outfit, regardless of results, that area of the game is something we always respect with France."
England are the only team still capable of completing a Grand Slam.