keeping a track up is somewhat easy, just deal with weeds, common erosion from the elements and cars, clearing it of the occasional rock, but ya, other than that, its easy, and even with the list i gave, heck, just do whats needed, ok tip time (i can thank Gex61 for it)

HOW TO PACK DIRT FOR JUMPS
first, step on the dirt to pack it
then water it down till the water starts to "puddle' on the surface, let it soak in
take a plastic sheet and lay it over the soil and take a lawn roller, car tire (they do work very good, i use an old racing slick)
roll the tire, lawn roller.... over it to pack it down (if using tire lean on it, helps a ton to pack it)
slide the plastic off carefully (don't lift, it can cause the dirt to stick, leave in clumps,,, disaster)
let jump dry for a bit
HAVE FUN JUMPING (this tip can be sucessfully used to pack down loose dirt to[8D])