340 EXPERIMENT STATION EECOED. 



gions, inclucling data relative tcrtlie cost of establishing and maintaining guaA-a 

 plantations. 



Lemon blossoms and why they fall off, J. E. Coit (Cal Cult., 36 {1911), 

 No. 23, p. 683, figs. If). — A preliminary study of the factors influencing the set- 

 ting of lemons leads the author to conclude that, other conditions beiug equal, 

 the annual dropping of blossoms and small lemons in May is due generally to 

 an overproduction of blossoms and fruit rather than to any pathological cause. 

 Experiments conducted this spring indicate that pollination of the blossoms of 

 lemons is not necessary for the setting of fruit and that the presence of bees 

 in lemon orchards may cause the lemon to contain too many seeds by bringing 

 about pollination and fertilization. 



A study of the growth of lemons leads the author to conclude that, contrary 

 to a common opinion among lemon growers, the lemons fruit on new growth of 

 the season instead of on old wood. The stems or peduncles growing on old, 

 interior limbs are classed as shortened branches bearing small foliar bracts 

 which represent abortive leaves. 



[Pineapple investigations], W. P. Kelley (Raivaii Sta. Rpt. 1910, pp. 

 14-16, 41--'f3, Jf5-50). — A progi-ess report on investigations with pineapple soils 

 and fertilizers, together with results of a study of the composition of Hawaiian 

 pineapples. 



In connection with the study of manganese in the soil as affecting the growth 

 of pineapples (E. S. R., 22, p. 240) experiments were made with a number of 

 field crops, garden vegetables, and fruit trees to determine whether they could 

 be grown in rotation with pineapples or replace pineapples in the manganiferous 

 soils. The manganese invariably caused a yellowing of all the leaves and a 

 premature falling of the lower leaves on all plants tested, the ultimate outcome 

 being a decidedly stunted growth and small yield. The root system in man- 

 ganiferous soils is peculiar in the length and fineness of the small roots. This 

 is attributed to the lack of resistance in the soils, which remain loose like 

 ashes no matter how frequently irrigated. 



; In the fertilizer experiments being conducted with pineapples, the plants 

 treated with dried blood or ammonium sulphate, superphosphate or reverted 

 phosphate, and sulphate of potash have from the first greatly exceeded all others. 

 Although the yields were not entirely satisfactory, these results suggest a 

 possible treatment for soils that contain limited quantities of manganese. Ai-eas 

 that contain 4 per cent or more of manganese are ill suited to pineapple growing. 

 The soil appears to be greatly benefited by the application of soluble phosphates, 

 whereas basic slag produces an increased tendency to a yellowing of the plants 

 as well as reduced yield. It is suggested that soluble phosphates may render 

 the manganiferous salts in the soil less soluble. The addition of lime, on the 

 other hand, results in the development of a more intense yellow color in the 

 plant and its -subsequent failure to produce fruit. The studies of manganese 

 relative to its solubility, its relation to other fertilizers, and its physiological 

 functions, etc., are to be continued. 



For the purpose of determining some of the facts regarding the composition 

 of pineapples as influenced by the stage of ripeness at which they were 

 gathered, analyses were made and are here reported of fruit normally ripened, 

 just before the beginning of the ripening process, ripened after being picked 

 green, when about one-fourth ripe, and when half ripe. The results show that 

 the sugar content of the fruit is derived exclusively from the leaves of the 

 plant and does not increase after the fruit has been removed from the plant. 

 In general it was found that the acidity increases with the sugar content and 

 that the average of the total sugars is about equal to that of pineapples from 

 Florida (E. S. R., 22, p. 640) and the West Indies. The sugar content of green 



