Paint Grass Slope Issues

I was using the paint tool to paint my grass on a landscape when I noticed whenever I go a little ways away from any slope, big or small, the grass completely disappears like this: http://imgur.com/a/Cg4IM

I switched to 4.16 and noticed the same issue. I’ve fiddled with many settings, with nothing working.

I’m also having the same issue with the foliage tool on slopes.