5IO 



Journal of Agricultural Research 



Vol. Xn, No. 8 



Table III. — Percentage of humus to depth of ;j feet in mulched basins in orange groves on 

 sandy loam soil. Experiment II 



Date. 



1915 



May 3 



Aug. 9 



Sept. 4 



Oct. 4 



Oct. 30 



Nov. 30 



Average for 191 5. ... 



1916. 



Mar. 17 



Apr. 17 



May 15 



June 16 



July 13 



Aug. 7 



Average for 1916 



Ratio, 1916 to 1915. . 



Basin treatment and jjercentage of humus. 



Alfalfa Manure Alfalfa Manure 

 alone. alone. and lime, and lime. 



O. 169 

 .128 

 . 129 

 • 230 

 .203 

 .185 



174 



251 

 227 

 129 

 216 



195 



175 



199 



I. 14 



o. 159 



. 121 

 . 146 

 .218 

 . 209 

 •159 



169 



241 

 220 

 180 

 213 

 167 

 296 



1.30 



D. 214 

 . 126 

 .187 

 .283 



•255 

 .181 



208 



.301 

 . 296 

 . 163 



•309 

 .244 



•243 



259 



1.24 



o. 196 



. 164 

 . 189 

 . 260 



•307 

 . 213 



221 



286 

 338 

 . 180 



248 

 309 



272 



23 



Experiment III. — In October, 191 5, a block of 60 trees in another 

 orange grove of heavy sandy loam soil was basined and mulched. The 

 basins were about 6 by 20 feet. The mulching materials used, the 

 quantity of each, and the percentage of humus in the soil are given in 

 Table IV. The percentages are averages to a depth of 3 feet. The 

 amount of bean straw used was not enough to cover the soil, and so did 

 not make an effective mulch. Some of these basins received in addition 

 to the mulching material, 100 pounds ground lime rock, analyzing about 

 90 per cent calcium carbonate. 



Table IV. — Average percentage of humus to a depth of 3 feet in mulched basins in an 

 orange grove on heavy sandy loam,. Experiment III 



