24 



Pounds. 



Tripa capa clara _ __. _ 14 



Tripa capa negra 23 



Total... ^ 



Tripa 21 



Yield of two-thirteenths of an acre 2'28 



yielii jier acre ___ _. 1. 4S2 



Samples of the light and medium wrappers were valued by fif^ar 

 factories in San Juan at §2.5(1 and 82, respectively, and one large fac- 

 tory offered SI. 50 a pound average. 



As a result of these experiments and observations in regard to larger 

 areas that have been grown under shade in Porto Rico it may safely 

 be said that shading increases the yield, quality, and iiercentage of 

 wrappers sufficiently to make shading a profitable bitsiuess, provid- 

 ing it is pi'acticed only on soils suitable for growing wrappers and the 

 crop is given the best of care throughout its growth and further treat- 

 ment in curing and fermentation. 



EXPERIMENTS "WITH FERTILIZERS. 



It was planned to try the eiTect of fertilizers at both Aguas Buenas 

 and Aibonito, but uncontrollable circumstances prevented the work at 

 the first-named place. At Aibonito, however, seven /^-acre plats 

 were laid oiit and treated as follows: 



Plan of fertilizer experiments. 



Plat No. 1. — No fertilizers. 



Plat No. 2. — 20 pounds sulphate of potash, 00 ponnds acid phosphate. 



Plat No. .3. — 30 ponnds sulphate of potash, 20 pounds nitrate of soda. 



Plat No. 4. — 60 ponnds acid pliosphate, 20 pounds nitrate of soda. 



Plat No. 5. — 60 pounds acid phosphate, 20 pounds sulphate of potash, and 



20 pounds nitrate of soda. 

 Plat No. (>. — 60 ponnds acid i)hosphate. 20 poimds sulphate of potash, 20 



pounds nitrate of soda, and 200 pounds lime. 

 Plat No. 7. — No fertilizers. 



The plats were all planted on the same day, and at a later date each 

 plat was i^hotographed for the purpose of recording the differences 

 in growth, which in some cases was very marked. Even the least 

 affected of the treated plats showed a small increase in growth over 

 the tintreated. By comparison, plats 2 and 4 were found to be equally 

 good, but much superior lo No. 1, which had no fertilizer. No. .3 was 

 much inferior to Nos. 2 and 4, but slightly better than No. 1. This 

 showed that the sulphate of potash and nitrate of soda com liined had 

 very little effect, and that acid phosphate when combined with either 

 of the others separately gave a marked effect. It seems, therefore, 

 that for growing tobacco on this soil acid phosphate as a manure is 



