40 



INDEX TO PAPERS ON PLANT SUBJECTS IN YEARBOOKS. 



Year- 

 Extract, book. Page. 



Present condition of grape culture in California 147 1898 551-562 



status of flax culture in the United Stales 109 1897 471-486 



nitrogen problem, paper 411 1906 125-136 



President pecan, history and description 450 1907 316 



Prevention and cause of pear blight 50, 57 1895 295-300 



Principal commercial plant fibers 321 1903 387-398 



Principles of pruning and care of wounds in woody plants 57 1895 257-26S 



Pringle plum, history and description 399 1905 503 



Producing beet sugar, methods of reducing the cost, paper 422 1906 265-278 



Production, crop, relation of soils 5 1894 129-164 



Productions, new citrus and pineapple, of the Department of 



Agriculture, paper 427 1906 329-346 



fruit, of the Department of Agriculture, paper. 383 1905 275-290 



Profits in sugar-beet growing 320 1903 408-409 



Progress in drug-plant cultivation, paper 401 1905 533-540 



some of the new work of the Bureau of Plant Indus- 

 try, paper 441 1907 139-148 



treatment of plant diseases in the United States 189 1899 191-199 



of Agriculture in the United States 179 1899 307-334 



commercial growing of plants under glass 191 1899 575-590 



economic and scientific agrostology 170 1899 347-366 



plant breeding in the United States 182 1899 465-490' 



"Project," basis of work in Bureau of Plant Industry 441 1907 139 



Proliferation, cotton 361 1904 487 



363 1904 500-502 



Promising new fruits, paper 283 1902 469-480 



330 1903 267-278 



356 1904 399-416 



399 1905 495-510 



429 1906 355-370 



450 1907 305-320 



Propagation, avocado 394 1905 441-443 



cerimap 394 1905 451 



guava 394 1905 453^54 



improved varieties of plains 446 1907 235 



mango 394 1905 445-447 



orange and other citrus fruits, methods 85 1896 471-488 



Protein in macaroni wheat 326 1903 331-334 



Prune, Splendor, history and description 330 1903 274-275 



Sugar, history and description 330 1903 275-276 



Pruning and grafting grapevines 281 1902 411 



thinning fruit trees 340 1904 176 



training of grapes 87 1896 499-542 



apple trees 230 1901 601-603 



fruit trees 246 1901 437-438 



lemon trees 453 1907 352-353 



principles, and care of wounds in woody plants 57 1895 257-268 



trees and other plants 145 1898 151-166 



shrubs 284 1902 517-518 



Public water supplies, contamination by algae, paper 262 1902 175-186 



Puerto Rico. See Porto Rico. 



Pumpkin, seeds 238 1901 251-252 



Pure seed investigation 18 1894 389-408 



Purple coneflower. See Coneflower, purple. ^ 



[Cir. 17] 



