Is urea still applied at some airports?

Urea is used as nitrogen-type fertilizer. We've used it on the
runway at low application rates to get thin skins of ice off it. The
urea will melt or cause evaporation of small patches of ice so that the
sun can warm those little patches of pavement and begin the warming
process that gets rid of the rest of the ice. Ice and/or snow will
reflect the sun's heat back into space.
Some have used soot applied to the snow or ice to absorb light
and start melting. Soot, though, is commonly found in ashes, which can
be corrosive.
Sawdust can be used to gain traction on ice. Only disadvantage
is its being tracked into the hangar, airplane, house, whatever.

Dan