Calcium and Magnesium are very important secondary nutrients and part of the chlorophyll molecule which is necessary for sugar formation. Inadequate amounts of Magnesium will first appear as a general loss of green color at bottoms of older leaves (inter veinal chlorosis). Continued deficiency will also affect younger leaves, followed by formation of lesions. Calcium and Magnesium deficiencies occur mostly in soils with a high pH over 8 and acidic soils with a pH less than 6.5. High levels of calcium and potassium will also reduce Magnesium uptake. Turf Applications: Soil lesling is necessary ta determine levels. Where Calcium and Magnesium leve ls are deficient or marginal, apply Cal Mag Max throughout the growing season. This can be added to any fertilizer spray solution.