Thank you for the thought and taking the time to comment. I am very aware of the dangers of rocks coming from a disc mower.  I do think the JD630 is much less likely to throw rocks than many other disc mower designs. There is a very heavy rubber belt-like curtain rather than the cloth on many other disc mowers. I do have the optional shoes on to get the cutting height up. The grass does come back a lot better at a higher (4 or 5") cutting height. There is also less chance of picking up rocks.

Thanks again for the reminder.