I believe coco liner can have high (relatively) levels of salt in it, based on where it comes from. I don't know that for certain, it was just something I was told once. I have no idea if there are varying degrees of coco, as Ive always used burlap. As for the aerial roots themselves, they are both a natural part of the plants design and a benefit for growers. They stabilize plants on structures and allow for additional water and nutrients to enter the plants system. However, you have to be very careful not to overdo it with fertilizers on the aerial roots, as you could end up burning them if the mix is too strong. I always spray my posts when I water, to moisten the burlap and air roots, and they continue to grow and develop. Keep in mind, that these are the same roots as are under the ground. When a cutting starts showing new root growth, its actually the air roots youre seeing. They just develop a type of thick skin if not kept moist, as they would be most of the time underground.
Ive seen entire plants completely removed from the soil by damage or rot, living just fine off the remaining air root systems that managed to get back into the earth. Do not underestimate the value of the air rooting systems.
