if you do as you want with this prop, and as geep suggested you will end up with a prop with tiling textures, the same tile will apply to each square of grass. you won't be able to draw lines on it unless you Remap your larger prop. becouse as soon as you drew a line on one of them, they would all get the same line in the same place. for what you want to do the suggestion of using a plain with noise displacement would actually be a lot easier becouse the plain would already be mapped to allow you to paint your stripes easily.