Neither is ideal but of the two dirt is preferable. Sand in a horse's digestive system can cause what is called 'sand colic'. It's real colic caused by an accumulation of sand in the horse's gut. If there is enough of it the vet can actually hear is with a stethoscope.
If you do have a dirt floor in you stall, if you can afford it place rubber matts over the dirt and then a thick layer of shavings or straw. This is the cleanest and best bedding for your horse. It does cost more but your horse will be happier and healthier.
it is DIRT
Sand, or sawdust/dirt.
Dirt sand and clay
Yes
anywhere theres land: sand, dirt, snow.
No sand does not have things that dirt does
sand because dirt has water in it but sand does not
Green beans grow better in soil.
Sand has no nutrients and vitamin C but soil does.
sand not dirt because dirt does not have healthy ingredients in it for the tortoise or turtle
sand
Sand 100%! Never use sawdust! Sawdust can severely damage a horse's lungs! And if the horse is pregnant, It can also damage the baby before it is even born! sand is almost just as bad but at the same time not nearly as bad. If I were you, I would use alfalfa, and lots of it. A woman I used to work for would only use that in her stalls, and when we would muck them, she would have us put more in there. She would always say, "I want to be able to eat off those stall floors." That is what I suggest for you and your horse.