HORTICULTURE. 635 



ous to citrus trees is uot well founded. The beneficial effect of fertilization on 

 the citrus groves throughout the island was more noticeable during the year 

 than ever before. Experiments are being conducted to determine whether the 

 time of blooming of the citrus trees can be influenced by the application of 

 fertilizers at cei'tain seasons of the year. 



Experiments with leguminous green-manure and orchartl cover crops were con- 

 tinued and a number of new varieties tested. Among the most promising of 

 those recently tested are a few varieties of Stizolobium received for trial from 

 the Office of Seed and Plant Introduction of this Department. The velvet and 

 I^yon beans have proved to be excellent cover crops, especially as a green 

 manure, in rotation with pineapples or on an othei'wise unoccupied field. They 

 are sometimes troublesome in groves, as they climb over the trees. During the 

 past two years the sword bean and pigeon pea have been tested as nitrogenous 

 manure crops and cover crops with pineapples by planting them in the i>iue- 

 apple beds. Both crops have a mox'e or less injurious effect on the growth of 

 the pines. More damage was done to the Cabezona variety than to the Red 

 Spanish, and the pigeon peas were more injurious than the sword beans in 

 every case. Where the sword beans had been allowed to grow during the wet 

 season only, the injury was the least. 



The cooperative fertilizer experiment with coconuts was continued. During 

 the past year four pickings of fruit were made, the last one being 16 months 

 after the first application of fertilizer. No beneficial effect from the fertilizer 

 has been observed thus far. 



Dynamiting for loosening the soil and facilitating drainage has been used in 

 a number of places in Porto Rico, both in land devoted to citrus trees and to 

 pineapples. Thus far no striking beneficial results have been observed from 

 the use of dynamiting. Where it has been tried in old groves and in i)ine- 

 apple fields no improvement has been noted that can be attributed to it. It is 

 believed that where there is a substratum that can be broken through or the 

 charges are placed so as to afford subsoil drainage from one loosened area to 

 another, dynamite should prove beneficial to the hea^y soils, as poor subsoil 

 drainage is one of the greatest hindrances to citrus culture in Porto Rico. 



Cultural directions for veg'etables and flowers, P. J. Westeb (Philippine 

 Bur. Agr. Circ. 25 {1913), pp. 5). — This popular circular contains general direc- 

 tions for the preparation and management of vegetable and flower gardens. 



The fresh vegetable trade in Germany, H. Michaelis (Arb. Deut. Landiv. 

 GeselL, No. 261 (lOl-i)^ PP- SO). — This embraces the results of a survey of the 

 marketing problems connected with the fresh vegetable industry in Germany. 

 The subject matter is discussed under the general headings of the development 

 of the German fresh vegetable industry, existing organizations for the sale of 

 vegetables, organizations for marketing vegetables in Holland, and recommenda- 

 tions for the improvement of trade conditions in Germany. 



Suggestions for the control of injurious insects and plant diseases, G. M. 

 Bentley (Tennessee Sta. Bui. 106 (1914), PP- 121-1^8, figs, ^i.— This bulletin 

 contains directions for the preparation and use of various insecticides and 

 fungicides in the control of the important injurious insects and plant diseases, 

 and also of herbicides. Attention is also called to preventive measures, such 

 as cultivation, drainage, time of planting, rotations, and the encouragement of 

 beneficial insects and birds. 



Fungicides and insecticides for Montana, H, E. Morris and J. R. Parker 

 (Montana Sta. Circ. 36 (19U), pp. 201-261, figs. ^).— This circular discusses 

 the composition, preparation, application, and cost of the more important fungi- 

 cides and insecticides adapted to Montana conditions. A spraying calendar 

 revised from a previous circular is also included (E. S. II., 28, p. 47). 



