Most deicers dry to a white powdery residue. This includes rock salt, urea, potassium chloride and blends of those materials. The two other deicers, magnesium chloride and calcium chloride, leave a clear brine solution. Regardless of the deicer, again, prevention is the best approach. Walk-off mats are one of the simplest yet most effective ways to cut down on tracking.
Studies show that at least four feet of mat is needed with six to ten feet for higher traffic areas.
All common deicers, even those used as fertilizers, have the potential to harm vegetation. However, studies show calcium chloride actually poses the least threat. The best way to protect trees, shrubs and grass is not to use too much. Deicers are not intended to melt every bit of precipitation and should always be used sparingly . For calcium chloride, it usually takes only takes two to four ounces per square yard to effectively undercut bonded ice and snow.