You will get the most out of your drawing when it's well organised. A proper layer setup, and usage, is one of the basic elements. Placing entities on the right layer requires a consistent way of working. With 'Hatch Designated' it will be a bit easier. When you are making a plan drawing with areas of grass you will make boundaries for those areas. You can place those boundaries on a layer named 'grass-b' or 'lawn-b', whatever works best for you. When you setup those layers you can setup layers to hatch them with as well. Those layers should be named 'grass-h' or 'lawn-h'. When you run 'Hatch Designated' and select the boundaries on 'grass-b' the command will hatch the boundaries and will put those hatches on 'grass-h'. That way you don't have to put the hatch on a layer yourself anymore. If you want you can set a designated hatch pattern, scale and rotation as well. Right after selecting the boundaries you can select a hatch. The pattern, scale and rotation of that hatch will be applied to the new hatches. The command will remember them for a next selection. With 'Hatch Designated' you can hatch your entire drawing at once without having to switch layers.