Heres the deal... A customer is having a wedding in July. He had a hard time dealing with the drought last year... has a roughly 14k lawn (about 11 in the back) and no automatic irrigation. I would like to apply Pre M to prevent crabgrass but would also like to aerorate (sp?) and apply seed so as to thicken up his lawn. How would applying the Pre M affect topseeding, if at all? Also, is this the recommended course of action?