84 Fooi> ynn I^.axts. 



trol, which is a customary practice about the second week 

 in June, and before any flowing which might be necessi- 

 tated by danger of frost. 



NITRATE AS FERTILIZER. 



What It Did For an Acre of Sug-ar Cane in Porto Rico. 



Abstract from Facts About Sugar, September 7, 1918. 



(The results of an interesting experiment conducted at Central 

 Aguirre, Porto Rico, during the season 1917-18, to check up the rela- 

 tive values of Nitrate of Soda, of Acid Phosphate, and of a mixture of 

 the two, as fertilizer for sugar cane, are described in the follouing 

 article. The accompanying illustrations and table show the striking 

 results obtained from the ii-re of the Nitrate. — En.) 



An Instructive Demonstration. 



A recent experiment conducted at Margarita field, 

 Hacienda Carmen of Central Aguirre, Porto Eico, 

 forcibly brings out the gain in sugar yield, with the 

 accompanying higher financial return resulting, when 

 Nitrate of Soda and acid phosphate were used, compared 

 with the returns when acid pho])hate was used alone. 



The test was made to determine the relative efficiency 

 of acid phospliate — which is the main constituent of the 

 ordinary brands of mixed fertilizer — as compared with 

 Nitrate of Soda. 



The cane was grown on adjoining one-acre plots. 

 Applications of the fertilizer materials were made on 

 July 23, 1917, and the cane was cut on May 27, 1918. On 

 one plot 400 pounds of acid phosphate was applied; on a 

 second 400 pounds each of acid pliosphate and Nitrate of 

 Soda; on a third, Nitrate of Soda alone, and on the 

 fourth, a check plot, no fertilizer was used. The results 

 obtained are shown in the following table : 



Confirms Hawaiiwi Practice. 



Sucrose. Purity Cane Sugar 



Acre Plots per '^Pn* P^"" ''•'"* yield tons yield tons 



1. Acid Phosphate l^.^O 02.50 24.96 .3.2 



2. Xitrate of Soda and Acid Plios- 



phate 17.38 91.50 38.00 4.7 



3. Xitrate of Soda alone 16.45 89.20 41.50 4.7 



4. Check ]dot — no fertilizer 17 . 55 91 . 40 30 . v 3 3.8 



