I was out spraying a lawn today when a neighbor asked me about spraying his lawn. He told me that he had already spread some Scott's fert with crabgrass control. The ai. was pendamethalin 1.95%. I mentioned that what i'm spraying is more highly concentrated than the scotts, which is penda as well. He asked if it would hurt the lawn if i sprayed a full rate on top of it. I told him probably would, but maybe a half rate should do good and not hurt it. Also he asked about doing fert on top of this too. What do you think? How bout the extra chemical, too?This is a fescue lawn, btw. Thanks.