Oftentimes, when horse facilities are plagued with smelly paddocks, it is due to the buildup of manure around the area. A good manure management strategy for all pastures, paddocks, and stalls is to remove the manure (don't forget wet bedding in stall situations) frequently. For stalls and small paddocks, daily removal of manure should rid the area of any annoying smells and pests. For pastures, drag harrowing the fields with a chain-link fence or other commercial pasture drag should help break up and dry manure piles. This helps to decrease smells, parasites, and other pests. You can also try sprinkling agricultural lime in the soiled areas to neutralize the odors if manure removal alone does not work.