Grass painted only within a circle on the terrain

When I try to paint grass on my terrain, I can only do so inside an arbitrary circle and not outside. I have played with every setting/brush to no effect.

It's not that grass is only painted in circle, it's that you don't see detail at certain distance. In terrain settings, increase Detail distance. Don't forget to turn it lower again when testing your game or it will be dog slow :-)

i had this problem before. you actually can put the grass there but you can not see that. unity has a setting in terrain settings that says in what distances you can see the grass and tree objects. change the detail settings to change the distance. this value should be different in editor and game. in the editor you can set it to a high distance to place details easily but in your game it should be a value suitable for your camera and performance. i think unity guys should put special settings for the editor seporately in the editor. creating a editor script to do this is not hard.