Huber, D.M. 1981 The use of fertilizers and organic amendments in the control of plant disease.. Handbook of Pest Management in Agriculture. Vol. I. (CRC Series in Agriculture). CRC Press Boca Raton, Florida 597 pp.

Notes: Purple scale is listed as one of the insect infestations influenced by magnesium. Mealybug and Pseudococcus comstocki are listed as insects influenced by nitrogen.