I often us the scatter grass tool, the lawn grass is absolutely useless for this (doesn't fill at all) so I'm forced to use the longer grass options. While they fill up nicely they are also too long for a lawn. So actually decreasing the size would help a lot to fix this and get the best of both worlds, however when you use path tracing grass height is somehow fixed at the standard 50%!!
So I either accept it (sometimes lowering the grass area completly to fake it) or go in and paint every bit of grass with a brush :(
Are there other solutions? Is this a known bug? Is it even a bug?