442 



INDEX 



Soluble silica, in soils, 70. 



Sonora wheat, 240. 



Sorauer, 12, 178, 1S3. 



Sorghums, 244. 



South Dakota, area, 26 ; deep and 

 fall plowing in, 195. 



South Dakota Station, dry-farming 

 in, 370 ; present status of dr3'- 

 farniing, 3S9. 



Sowing, see also Ger?nination, 205— 

 228, 415; and seed-bed, 212 

 failures due to, 205 ; implements 

 for sowing, 317 ; method of, 225 

 time of, 212; in fall, 212 ; in fall 

 disadvantages of, 214 ; in fall 

 when preferable, 215 ; in fall and 

 fallowing, 218; in fall and root 

 system, 216; in fall, right time 

 of, 216 ; in spring, when prefer- 

 able, 215; depth of, 220; quantity 

 for, 222 ; in various sections, 215. 



Spalding, 178. 



Spring, cultivation in early, 159; 

 if wet, causes loss of soil-water, 

 160. 



Springs, source of water, 334. 



Spruce, on dry-farms, 253. 



State aid, for dry-farni studies, 368. 



Steam, machinery in dry-farming, 

 321. 



Stems, proportion of, 260, 261. 



Stewart, 284. 



Stewart arid Greaves, 190, 263, 271. 



''St. John's Bread," on dry-farms, 

 252. 



Stockbridgc, 154. 



Stomata, description, number, and 

 function, 172-174. 



Stooling, 223. 



Storing water, in soil, 94 ; depend- 

 ent on pore-space, 102 ; by fall 

 plowing, 126; by deep plowing, 

 125; in Great Plains soils, 122. 



Straw, from dry-farms very nutri- 

 tious, 275 ; header straw to 

 retard evaporation. 150; header 

 stubble conserves soil-water, 155; 



not to be burned, 156 ; ratio 

 straw to kernels, IS; ratio to 

 grain and climate, 261 ; relation 

 of roots to, 216. 



Strawbridge, 393. 



Stubble, see also Header, Straw ; 

 decay of header, 191, 230; for 

 header and fertilit3% 290 ; header 

 stubble and fertility, 228 ; header 

 stubble and humus, 198 ; value 

 of header stubble in transpira- 

 tion, 191. 



Sub-humid area, and dry-farming, 

 29; defined, 24. 



Sub-Pacific, type of rainfall, 39. 



Subsoil, characteristics of arid, 60 ; 

 distinction between soil and, 61 ; 

 importance of moist, 116; may 

 be turned up in arid countries, 

 126; meaning in arid countries, 

 .59. 



Subsoiling, and dry-farming, 126; 

 an advantage of, 141 ; how 

 accomplished, 308. 



Subsurface packer, 316; invented, 

 302." 



Subsurface packing, disadvantages 

 of, 364. 



Subterranean, water, quantity of, 

 338. 



Sugar beefs, on dry-farms, 254 ; on 

 irrigated farms, 236 ; variation 

 in composition, 268 ; water and 

 yield, 346. 



Summer rains, cause loss of soil- 

 water, 160 ; sometimes detri- 

 mental, 130. 



Summer tillage, see Cultivation and 

 Fallowing. 



Sunflowers, pounds water for one 

 pound, 14. 



Sunlight, effect on transpiration, 

 177. 



Sunshine, over dr;\'-farm territory, 

 46. 



Swedish Select oats, 241. 



Sycamore fig, on dry-farms, 252. 



