202 



PLANT GROWTH 



Salts, mineral, 41-45, 47, 50, 55 



Scarification, 190 



Scion, 68-70, 70 



Sedums, 116 



Seed 



albuminous, 7, 9, 10 



bean, 8 



characteristics, 6 



coat, 7 



corn, 7 



definition of, 6 



dicotyledon, 8, 10 



dissemination, 107 



dormant, 6 



exalbuminous, 8, 10 



germination, 15, 19 



iris, 9 



lengthwise section of, 7 



longevity, 11 



monocotyledonous, 7 , 10 



parts of, 7-10 



planting, 11, 18, 19 



propagation, 66 



selection, 10 



soaking, 15 



storage conditions, 7 



testing, 20 



treatment, 147 



vitality, 10 



weed, 104-108 

 Seedling, 11, /^, 13, 105, PI. I 



bean, 13 



definition, 14 



growth, 14, 20, PI. XV 



hollyhock, 12 



oats, 12 



pea, 13, PI. XV 

 Selenium, 43,98, 164 

 Self-pollination, 119 

 Sepal, 114, 115 

 Shade, 181 

 Shoot, 92-96 

 Short-day plants, 84 

 Snapdragon, 113 

 Sodium chlorate, 111 

 Soil, 46-52, 158-171 



acidity, 109, 159, 171 



air, 50 



air dry, 49 



alkaline, 159, 171 



bacteria, 51 



components, 3, 46 



conservation, 161, 162 



drainage, 160 



erosion, 161, 162 



fine, 50 



humus, 158, 160, 161 



improvement, 47-52, 158-163 



living organisms, 161 



moisture, 15, 89-91, PI. XVI 



mulches, 159-161 



neutral, 159 



organisms, 158-162 



oxygen, 16 



sandy, 46, 50 



silt, 46 



solution, 42 



temperature, 16 



testing, 159, 167 



texture, 158 



water, 48, 49 



water-holding capacity, 46, 47, 49, 51, 

 160 

 Soilless gardening, 172, 173 

 Sperms, 117 

 Spikelets, 118 

 Spores, 98-100 

 Sprays and spraying, 97-103, 157 



arsenic, 43, 101 



copper, 43 



DDT, 101 



hellebore, 101 



kerosene, 101 



lead, 101 



lime sulphur, 101 



Paris green, 101 



pyrethrum, 101 



rotenone, 101 



soap emulsion, 101 



tobacco, 101 

 Spring beauty, 189 

 Stamen, 114, 116 

 Standard, 117 

 Starch grains, 76 

 Stem, 53-58 



bark, 55 



cambium, 54, 55 



