INDEX. 669 



Roads — Continued. 



forest— Page. 



construction, mileage, Januan,- to December, 1919 241-245 



cooperative construct ion 515 



provision in Federal-aid road act 242 



legislation, suggestions 507-509 



management and economics, work 520-522 



materials — 



scarcity and increased prices 492-510 



tests and researches 5ir>-520 



mileage and types, summary for 1917, 1918, 1919, and 1920 507 



models and exhibits ' 521-522 



National Forests — 



mileage and needs 45 



work 510-515 



t\'pe, selection, discussion 498-499 



See also Highways. 



Robins, destructive haVnts 357 



Rock, road-building, examination and classifications 518 



Rocky Mountain States, search for pine blister rust 215 



Rodents — 



control 347-353, 366 



destruction — 



of cotton 350 



of irrigation ditches 350 



injury to orchards 349, 350, 351 



See also Gophers: Ground squirrels: Mice: Rats: Woodchucks. 



Root-rot, peas, control 209 



Roots, plant, infection with nemas, dangers in importations 216 



storage investigations 175-176 



Rot- 

 brown, of prunes and cherries, control 219 



root, of peas, control 209 



stem-end, citrus, studies 218 



Rotations, crop, study 33 



Rots. corn, symptoms, lo^es and control 198-199 



Roundworms, sheep and nogs, investigations 148-150 



Rumfx nbifssinicus , growing in Florida 186 



Rural engineering, investigations 527-528 



Rust, blister, white pine, cause and control 211-215 



Rusts. whea;t, causes, forms, and control 202-204 



Rye- 

 acreage and production, 1914-1920 5,6,9 



leaf nist 204 



Rynchosporium secalis, cause of barley scald 201 



Saccharin, food use. control 260-261 



Salaries, scientific employees, discussion by Secretary 59-61, 62 



Salmon, spoilage studies. 260, 270, 273 



Salting, cattle on ranges, methods 253 



Samples, examination by Chemistry Bureau for other departments 284-285 



San I'rancisco-Point Reyes-Mt. Tamalpais telegraph station, service 77 



Santonica, adulteration 266 



Sarcoptic mange, control in horses 150 



Satsuma orange growing in Alabama 175, 176 



Sawdust, utilization for stock feed 248 



Scab- 

 apples and pears, control 219 



citrus, control 218 



wheat, caiises and control 199-200 



Scabies, cattle and sheep, eradication, dippings, etc 129 



Scald- 

 apples in storage, investigation 219 



barley, investigations 201 



Schfdius kuvanne, parasite of gipsy moth 327 



Scientific and regulatory work, suggestion for directors 60-61 



Scientists, department, contributions to outside publications 385-386 



Screens, wire, tests 336 



