pH DETERMINATION IN PLANT TISSUE.

In a recent investigation1 a procedure was found that permitted fairly accurate determinations of the pH of soils of low moisture percentages. One of the essentials of the method was the use of a horn spoon in spreading the moisture or soil films uniformly throughout the rather dry soil mass. When plant tissue is finely cut in a grinder, relatively few of the cells are actually opened. The important fact is that the contents of the cut cells is smeared over the uncut groups of cells. On account of the somewhat analogous nature of the state of the soil and of the finely divided plant tissue, it appeared highly probable that the same methods that were applied in the determination of the pH of soils could be applied equally as well in the pH determination of plant tissue.