Originally Posted by Do-Over

This "dirt" you speak of is actually top soil... or the top 6-8 inches of decomposed organics that make up the top layer of any piece of land that has sat undisturbed for any length of time. This material will hold water like a sponge rather than shed it like a waxed car. The problem with using all "dirt" is that it won't compact to seal out water and create a sturdy base. Any track made from topsoil is temporary at best as it will wash out quickly. I've been an excavator for almost 15 years and if you want something to hold up you must build with clay and compact it in. I've been wanting lately to build a track by combining about 70% clay with 30% topsoil which I think would make a solid base and still be a little forgiving on the cars and the tires.