The vegetation in the desert are cactus and dry grass.The cactus is very important because it is used for shelter and for water. Owls live in the cactus, which is really odd. Dry grass is used for shelter for reptiles like snakes.That is the vegetation in the desert.he vegetation in the desert is very small because of its climate it is very hot and dry the only thing that can grow there is cacus and the cactus grow around 6-8 inches tall. You can cut open a cactus and drink the water from the spikes by rubing it in your mouth.