Critical values of the cation-quotients in the leaves for the estimation of relative deficiencies of K (with regard to Ca) and Mg (with regard to K) for deciduous trees.
| Normal | Possible deficiency | Deficiency | |
|---|---|---|---|
| K/Ca | 3.5-1.0 | 0.5-1.0 | > 0.5 |
| K/Mg | 1-to 9 | 7 to 9-12 | 12-20 |