Jeff, I did take some of the superficial layer off but I have noticed that the majority of the roots in all of my air layers so far are coming out of the untouched parts. So, I am actually going to try air layering without taking off the superficial layer to see what would happen.
Moonlight, thanks! I am using Lambert's Organic Potting Soil from Home Depot for my air layers. I also use those packing plastics filled with air to contain the soil. That's the plastic you see in the first picture.