654 INDEX, 



Page. 



Phosphoric acid, manufacture, investigations 241 



Photographic work 



Publications Division, summary, 1919 319 



Roads Bureau, 1919 414 



Photography, dyas improvement and use 231 



Phylloxera, grape, investigations 252 



Pickles, spoilage, studies 229 



Pig clubs, enrollment and membership. . 83 



Pine- 

 western, beetle, studies 259 



white, blister rust, cause and control 175-176 



Plant- 

 chemistry, studies 228 



Industry Bureau 



Library, work, 1919 343,344-345,347,348,349 



report of Chief, 1919 176 



specialists, cooperative work 386 



products, imported, inspection 528-529 



Quarantine 



Act, enforcement, 1919 482 



District of Columbia, need 532 



foreign and domestic lists 533-536 



Plants- 

 breeding experiments, 1919 150-152 



diseases, investigations, 1919 168-176 



imported, inspection 528-529 



introductions, inspection 159 



mail shipments, terminal inspection 529 



poisonous to live stock, investigations 123 



Plywood, flexible, development by forest service 205, 206 



Poisoning predatory animals, methods and results 277 



Poisonous plants, investigations 123 



Pork production forecast, 1919, and estimates, 1909-1919 5, 8 



Port inspection service, enlargement, need 531-532 



Porto Rico Experiment Station, work, 1919 363-364 



Posts, protection after cutting 259 



Potash 



resources, investigations, Soils Bureau 241-245 



sources, investigations 165 



Potato 



diseases, investigations 172 



wart, control work, 1919 517-519 



Potatoes 



grading, need of national standards 438 



growing, varieties investigations 147-148 



insects injurious, investigations 256 



varieties immune to potato wart 519 



yield per acre, increase since 1908 14, 15 



Poultry 



breeding and feeding investigations, 1919, parasites, etc 87-89, 122-123 



clubs, enrollment and work 89 



diseases, outbreaks and control 122-123 



feeding experiments , . . 87-88 



investigations, 1919, Chemistry Bureau - 222 



products, market news service 449 



work of county agents. North and West 383 



Prairie dogs, control work 279 



Preservatives, wood, research studies 206 



Printing- 

 Section, Publications Division 315-316 



Weather Bureau, work of 1919 68-70 



work, appropriation and expenditures. 1919 303, 305-310 



Production cost, studies, work of Farm Management Office, 1919 463, 464 



Products, surplus, estimates, demand for 329 



Proof, handling in Publications Division 303-305 



Proteins, chemistry and nutritive value, studies 220 



Pruning, citrus trees, experiments 142-143 



Public Roads. See Roads. 



