In a natural setting, feminization is done by the transfer of the pollen of the male to the female, guaranteeing the transfer of hereditary information. Review By Diamondave. However, grassy weeds such as crabgrass usually resist the action of weed and feed.  Source: <a href=https://www.grogheads.com/forums/index.php?topic=26039.8160>https://www.grogheads.com/forums/index.php?topic=26039.8160</a>