When I rode in the desert (hard ground with lots of stones), I picked out my horses hooves before and after every ride, as did every other rider at the barn, as far as I could tell.
Here in Ireland where the ground is very soft and there are fewer stones I pick out my horse's hooves before every ride, but not after. However, I noticed that I am the ONLY out of about 40 boarders who does this on a regular, frequent basis.
It take all of 2 minutes and can make the difference between a ridable horse and a lame horse.
catsandhorses is an American living in Ireland and riding mostly XC with "Bob". She is looking forward to buying a new horse when she returns to the U.S. in January'2012!