HOETIOULTUBB. 643 



of fertilizer experiments with oranges and lemons which were started by the 

 California Citrus Station in 1907. 



The results thus far indicate very strongly the importance of nitrogen ferti- 

 lization and the desirability of using nitrogen from organic sources. Potash 

 appears to be unnecessary for the fertilization of young groves, and it is 

 doubtful whether phosphoric acid is required in such large quantities as 

 ordinarily are used. In lieu of further experimental results the author con- 

 cludes that in general one of the factors of fundamental importance in citrus 

 groves is to increase the amount of organic matter in the soil. This can prob- 

 ably best be done by the regular use of a winter cover crop such as Melilotus 

 or purple vetch and the application of manure, alfalfa hay, bean straw, and 

 similar materials as fertilizers. 



Suggestions on coffee planting for Porto Rico, T. B. McClelland {Porto 

 Rico Sta. Circ. 15 {1915), Spanish ed., pp. 23 pis. 4, fiff. 1). — A Spanish edition 

 of the circular previously noted (E. S. R., 28, p. 237). 



Coffee: Its cultivation and manuring in South India, R. D. Anstead {Dept. 

 Agr. Ml/sore, Gen. 8er. Bui. 6 {1915), pp. ^S, fig. 1). — A practical treatise on 

 coffee culture, the introductory chapter of which discusses the botany of the 

 coffee plant. The succeeding chapters deal with planting the estate, selection 

 of seed, nurseries, planting out, supplies, cultivation and preparation of the 

 soil, renovation of old coffee, draining, shade, regulation of shade, pruning, 

 weeding, mulching, humus, manurial value of mulch, manuring of coffee, 

 valuation of manures, mixing of fertilizers, the use of lime, green manuring, and 

 handling the crop. 



Notes on the spraying of tea, E. A. Andrews and A. C. Tunstall {Indian 

 Tea Assoc. [Pamphlet] 1 {1915), pp. iy+15, pis. 9). — This work discusses the 

 more important insect pests and fungus diseases of the tea plant and gives 

 directions for the preparation and use of sprays for their control. 



Bearing dates for grafted shagbark. — A new method for grafting nut 

 trees, R. T. Moeeis {A^ner. Nut Jour., 2 {1915), No. 6, p. 87).— After briefly 

 noting that Taylor grafts upou a top-worked shagbark stock came into flower 

 the fourth year, the author describes a new method of grafting herbaceous 

 grafts of shagbark hickory and English walnuts which has been used the 

 present spring. 



The method consists in mixing one part of commercial grape juice with three 

 parts of water and dipping the grafting knife into this solution just in advance 

 of cutting the scions or stock. The solution bathes the cut surface and not only 

 prevents instantaneous drying of the surface, but also inhibits the enzymic action 

 which otherwise takes place very rapidly with the effect of discoloring the cut 

 surfaces. The grafts were all made according to the side-cleft method. Al- 

 though no conclusive results have been secured as yet, scions not more than 2 

 in. in length gave so much promise of living two weeks after the grafting 

 period that the method is described with a view to encouraging further experi- 

 ments along this line. 



The industrial cultivation of aromatic plants for essences and medicines, 

 C. Craveri {Coltivazione Industriale delle Piante Aromatiche da Essenze e 

 Medicinali. Milan: Ulrico Hoepli, 19U, pp. XIX+S07, pis. 24, figs. 71).— A 

 practical manual on the culture of essential and medicinal plants. 



Part 1 contains general instructions relative to the selection and preparation 

 of soils, nursery and seed-bed practices, methods of propagation, cultural opera- 

 tions, harvesting, marketing, drying, etc. Part 2 takes up specifically the 

 botanical characteristics, cultivation, method of harvesting, and preparation 

 and uses of various plants. Part 3 treats of diseases and insect pests and 





