With the greatly appreciated moisture we have received already this winter and my sidewalk being slick several mornings this week, I thought it would be a nice reminder to discuss ice melts and the damage they can cause.
There are many different brands of ice melts available in today's market. There are five main materials that are used in chemical de-icers: calcium chloride, sodium chloride (table salt), potassium chloride, urea, and calcium magnesium acetate. Calcium chloride is the traditional ice-melting product. Though it will melt ice at negative 25 degrees Fahrenheit, it will form slippery, slimy surfaces on concrete and other hard surfaces. Plants are not likely to be harmed unless excessive amounts are used.
Rock salt is sodium chloride and is the least expensive material available. It is effective to approximately 12 degrees Fahrenheit, but can damage soils, plants and metals.
Potassium chloride can also cause serious plant injury when washed or splashed on plant foliage. Both calcium chloride and potassium chloride can damage the roots of plants.
Urea (carbonyl diamide) is a fertilizer that is sometimes used to melt ice. Though it is only about 10% as corrosive as sodium chloride, it can contaminate ground and surface water with nitrates. Urea is effective to about 21 degrees Fahrenheit.
Calcium magnesium (CMA) is a newer product and is made from dolomitic limestone and acetic acid (the principal compound of vinegar). CMA works differently than the other materials in that it does not form brine like salt but rather helps prevent snow particles from sticking to each other on the road surface. It has little effect on plant growth or concrete surfaces.
Using these products sparingly should cause little injury. Problems arise when they are used excessively or there is not adequate rainfall to wash or leach the material from the area. To protect concrete surfaces, water could be sprayed to wash off excessive during days or warmer temperatures above freezing. Keeping the products away from plant foliage and grass along walkways will also help prevent plant damage and burn. Many times the damage is not seen immediately but noticed next spring or summer.
For more information on de-icers, contact the Ford County Extension Office at 620.227.4542 or visit us online at www.ford.ksu.edu.