we had the gardener over for 2 days straight cutting the grass down almost to the dirt. took 3 truckloads to get it all removed, the mower they were using primarily was a modified beast of a mower with a similar blade. had a 13 hp vertical shaft engine on it and a blade that looked very similar. I dont know what type of grass my parents have but the stuff was about 4 in thick and about 3" of that was just brown root looking stuff. Funny thing is after cutting and removing all that the grass was nice and green and even looking a week later ~shrug