FIG. 22. Relation between soil temperature, potassium excess (in relation to the equivalent total of calcium and magnesium) and incidence of grass tetany
N.B. Cf. Table 21 concerning the influence of the ratio on the incidence of grass tetany.
    2. Cf. Figs. 20 and 21 for the influence of temperature on the incidence of tetany.
From KEMP