Agriculture 164 Landscape architecture 145 Soils 137 Timber 127 Forests and forestry 125 Environmental aspects 124 Wood 105 Forest management 95 Anatomy 94 Soil science 93 Landscape design 82 Sustainable agriculture 72 Landscape gardening 69 Economic aspects 68 Gardens 67 Gardening 64 Research 62 Control 57 Crops 57 Management 54 History 52 Soil erosion 50 Agricultural biotechnology 49 Design 48 Soil management 46 Fruit 43 Soil conservation 42 National parks and reserves 41 Agricultural ecology 39 Encyclopedias 38