and when it comes to minerals, if a plant cant uptake them in their roots, we cant use them. the minerals from trees are the finest and best for us. minerals from fast growing plants are less so. plants that remain from year to year are better than those which must come from seed every season. for example, the sunflower can be used to actually clean a plot of ground of toxins, that is how good they are at absorbing stuff we shouldnt have. that is why sunflower seeds or oil must be organic(which certifies the ground as well) or they are not even worth it.