AdWords Content Network Question

[bomo]

Does anyone know if there is a way to enable or disable the content network at the ad group level? Or, is this only manageable at the campaign level? I know I could split out a new campaign, but, for various reasons, prefer not to do this. For now, I have placed a very low bid for the content network ($0.01) for one of the ad groups I want to keep out of the content network - will this have an adverse effect on the ad group as a whole? Thanks!