Related by context. Frequent words. (Click for all words.) 77 nitrogen fertilizer 65 fertilizer 64 fertilizers 62 nitrogen 60 phosphate fertilizer 59 chemical fertilizers 57 urea 57 synthetic fertilizers 56 Nitrogen 55 glyphosate 54 potash fertilizer 54 cereal grains 53 Glyphosate 53 nitrous oxide emissions 53 crop residues 53 manures 52 Atrazine 52 Fertilizer 52 fumigants 52 herbicides 52 pesticides 52 insecticides 51 nitrogen phosphorus 51 feedstock 51 oilseed crops 51 legumes 51 phosphates 50 agrochemicals 50 phosphorus 50 fertilizers pesticides 50 urea fertilizer 50 fungicides 50 mulches 50 tall fescue 49 Ammonia 49 soil pH 49 soybean meal 49 crop yields 49 propylene oxide 49 organic fertilizer 49 organic fertilizers 49 polyols 49 Nitrates 49 monocultures 49 Insecticides 49 tillage 48 chicken manure 48 ethanol 48 nutrient 48 herbicide 48 Herbicide 48 ammonium 48 organic acids 48 cereal crops 48 surfactants 48 biofuel crops 48 pyrethrum 48 corn gluten 48 citric acid 48 fungicide 48 soil compaction 48 soy bean 47 sulphate 47 starch 47 distillers grains 47 corn silage 47 chemicals 47 toxic pesticides 47 silage 47 soils 47 methyl bromide 47 pesticide 47 atrazine 47 soil fertility 47 carbon dioxide 47 photosynthesis 47 Miscanthus 47 soda ash 47 Phosphates 47 ammonia 46 red clover 46 fertilize 46 rapeseed 46 Feedstock 46 pigweed 46 corn ethanol 46 Urea 46 biofuels 46 pesticides herbicides 46 agro chemicals 46 insecticide 46 biofuel 46 grasses 46 crop nutrient 46 crop residue 46 soyabeans 46 Polystyrene 46 woody plants 46 Fertilizers 46 Phosphorus 46 alfalfa hay