John Aalberg wrote an article for FIS. It well written and I don’t think I can add to it. See it here.
Quick summary:
- Salting should be used to save the competition (i.e. make it fair and safe), not just to speed up the snow or make skiing easier.
- Use in warm conditions – 0C, 32F and above.
- Works best for snow with significant water content. If you can make a snowball, salting may work for you.
- Test a small area before committing to covering your whole course.
- Allow time for the salt to work before skiing on it. Typically this is 45 minutes to an hour depending on a lot of other factors.
This event was the World Cup at Soldier Hollow, February 2019. The temperatures were right on the edge of freezing. It was a challenge to keep the course in shape.