 Also, consumption of most root vegetables involves uprooting and killing the entire plant, in contrast to consumption of most other terrestrial vegetables, upon which the plant lives on after plucking the vegetables (or it was seasonally supposed to wither away anyway).Mushrooms, fungi and yeasts are forbidden because they are parasites, grow in non-hygienic environments, and may harbour other life forms.Alfalfa is the only known plant that contains vitamin D2, which they may use directly or make vitamin D2 supplements from.