“…not all, but a large number of plant diseases can be alleviated just by means of a rational manuring. What is needed is just that the manuring adds calcium to the soil. For calcium to have a healing effect, however, it has to be calcium from something living; we cannot evade the organic realm….
“Now, one plant that contains plenty of calcium is the oak. Seventy-seven percent of its substance consists of finely distributed calcium. And oak bark, in particular represents a kind of intermediate product between the plant and the living earth element, in the same sense as I already described the kinship between bark and the living earth. Of the many forms in which calcium can appear, the calcium structure of oak bark is the most ideal. Calcium…. creates order when the etheric body is working too strongly, so that astrality cannot influence whatever organic entity is involved…. when we want a rampant etheric development to contract in a beautiful and regular manner…then we need to use calcium in the particular form in which it is found in oak bark.
“…we collect oak bark…. Then we chop it up until it is a crumb-like consistency, and put it into a skull from any one of our domestic animals…and finally close up the skull, preferably with a piece of bone. Next we place the skull in a relatively shallow hole in the ground, cover it with loose peat, and set up some pipe or gutter so that as much rainwater as possible flows into the hole…. Then add some kind of plant matter that will decay, so that the oak bark in its bony container lies in this organic muck for the whole winter, or better still for the whole autumn and winter…. When this material is added to your manure pile, it will truly provide the forces to prevent or arrest harmful plant diseases.”
Article Repost from R. Steiner, Agriculture, pp. 100-101, tr. C.E. Creeger and M. Gardner.