Cartilage is necessary in the wall of the trachea because it supports the trachea and keeps it open at all times. New born babies do not have these rings of cartilage around t … heir trachea, which is why their heads need to always be supported carefully. 2 people found this useful.xists and is an alternate of. Merge this question into. Split and merge into it. Answer by Koala coco. Confidence votes 43. The cartilage is necessary to hold the trachea open. The pressures of the air moving in and out of the lungs would collapse the trachea if there was nothing to hold it open.