Pine tree roots

I didn't know where to post this so that's why I'm here..

My property is lined w/ pine trees and they have invaded my yard..

I'm running out of blades for my riding mower.. and I'm afraid of bending the shaft after hitting these bad boys..

My soil is top soil over sand.. but the top soil is eroding away and the roots are popping up..

I tried to chain saw the roots but the chain didn't last very long in the sand..

A friend suggested a masonary wheel on a "skil saw"?? seems like it would work??

Anyone have any suggestions??

I hate to get a load of top soil, just to watch it wash away.. thought about "rocking" it.. but I like my grass..

HELP..