536 EXPEKIMENT STATION EECORD. 



compared with 15.8 after Bourbou. lu the fifth rattoon crop, White Trans- 

 parent and B 147 yielded 17.2 and 14.3 tons of cane per acre, respectively, on 

 the no-nitrogen plats, 24.8 and 21.5 tons after an application of 200 lbs. of 

 sulphate of ammonia, and 26 and 29.3 tons after an application of 400 lbs. of 

 the sulphate. Similar results were obtained with the second and third rattoon 

 crops of other varieties, the yields of Bourbon grown continuously being 1.3, 

 1.6, and 4.7 tons of cane per acre respectively on the no-, low-, and high- 

 nitrogen plats. 



On plats that have been receiving nitrogen continuously for 16 years, pud- 

 dling from the use of nitrate of soda seems more likely to prove injurious than 

 the souring action of sulphate of ammonia. The substitution of the nitrate for 

 the sulphate on the unlimed land was attended by a reduction of the increase 

 due to nitrogen from 13.1 to 8.5 tons of cane i>er acre, while the reverse substi- 

 tution " increased the excess yield over the not manured plats from 6.9 to 8.5 

 tons." On limed land these substitutions produced, respectively, a decrease from 

 13 tons to 6.7 tons per acre and an increase of ,2.7 tons. The continuous use of 

 nitrate of soda produced far more noticeable ill effects than that of sulphate of 

 ammonia, especially in very wet seasons. Soils which have been fertilized con- 

 tinuously for 30 to 50 years with the sulphate gave an alkaline reaction in 

 the majority of cases. 



The average yields on no-phosphate and slag-phosphate plats were 23.7 and 

 26.2 tons of cane per acre, respectively. Other tests of phosphates gave nega- 

 tive results which the author regards as " possibly due to experimental error 

 incidental to the comparatively small number (12) of comparisons made." 



Tables show the results of these experiments and of trials of new varieties. 

 These data are so grouped as to show the influence, if any, of the female 

 parentage of the variety. 



The plats were also arranged in such a way as to show the effects of the use 

 of increasing proportions of nitrogenous fertilizer, especially sulphate of 

 ammonia. Sixty lbs. of nitrogen in sulphate of ammonia and in nitrate of 

 soda produced yields of 22.7 and 18 tons per acre, respectively, as compared 

 with 14.4 tons on the no-nitrogen plat. With 11 varieties, the average yields 

 after applications of 150, 300, and 450 lbs. of sulphate of ammonia were 19.8, 

 23, and 23.9 tons of cane per acre, respectively, as compared with 15.4 tons on 

 the no-nitrogen plats. With 8 of the varieties, 375 lbs. per acre of nitrate of 

 soda were used and gave low^er results than either of the higher applications of 

 sulphate. In another test of 14 varieties 300 and 450 lbs. of sulphate of am- 

 monia were followed by average yields of 21 and 29.7 tons of canes per acre, 

 respectively, as compared with 12.4 tons on the no-nitrogen plats. 



Regarding the sugar yield of White Transparent as 100 on the Brickdam 

 field, D 4397 of Bourbon parentage, D 790, D 1119, and D 1082 gave yields 

 ranging from 151 to 185. B 208 gave juice rich in saccharose and high in purity, 

 but was not high in field results. Studies are given of the color variants of 

 B 208 and other varieties. Tables give the parentage, field yields, pounds of 

 sugar per gallon, and tons of sugar per acre obtained, for each of a large 

 number of the newer varieties tested. 



In pot and plat experiments with nitrobacterine for sugar cane, negative 

 results were obtained. When the highest probable errors due to soil and other 

 differences were deducted, the increased yield of rice after phosphates had 

 been used in former years was 5.1 per cent, after sulphate of potash and lime 

 the preceding year 8.2 and 13.9 per cent, respectively, after sulphate of potash 

 preceded by phosphates in former years 12 per cent, and after lime in 1908 

 preceded by phosphates in earlier years 11.5 per cent. Continuation of this 



