Fertilizers 9 Micronutrients 9 Remote sensing 9 Ion exchange in soils 8 Macronutrients 8 Soil fertility of plant nutrition 8 application 8 peyde 8 soil acidity 8 Plants 7 methods 6 Plant diseases 5 Plants, Medicinal 5 Herbs 4 History and criticism 4 Plant Breeding and Genetics 4 metabolism 4 Colonies in literature 3 Dietary Supplements 3 Drug-herb interactions 3 English literature 3 Herb-Drug Interactions 3 Imperialism in literature 3 Literature and history 3 Medicinal plants -- Periodicals-- Herbs -- Periodicals-- Spices -- Periodicals 3 PLANT PHYSIOLOGY 3 Pathology, Clinical 3 Phytochemicals 3 Phytotherapy 3 Plant Pests, (New March 2000) 3