50 JOURNAL OF AGRICULTURE OF P. R. 



of installing a systera of terraces, which will retain the soil around 

 the roots; otherwise such sites are better avoided, or abandoned if 

 already planted. 



THE NURSERY AND PLANTING STOCK. 



Too much attention cannot be given to selection of planting stock, 

 since a productive grove is hardly possible without a solid founda- 

 tion in the way of healthy trees from the nursery. "Where time is 

 available it will pay each grower to produce his own trees, thus as- 

 suring himself of healthy, vigorous trees of known variety and pro- 

 ductive parentage. If this is not possible, a careful inspection be- 

 fore purchasing should be made of the nursery from which the trees 

 are to come, to make certain that they are free of serious diseases or 

 insect pests. Tn the event that diseases or ingects are present, 

 thorough spraying, pruning, or other corrective measures should be 

 insisted upon before delivery. In addition the nurseryman should 

 give a written guarantee as to variety. 



In establishing nurseries, a site as far as possible from existing 

 groves should be selected, in order that the rapidly growing seed- 

 lings may be kept free from infection by disease, or infestation by 

 insects. The custom of planting nursery stock between the gTOve 

 trees is particularly undersirable, not only because of the disease 

 problems, but for other important considerations as well. 



It need hardly be said that all possible care in cultivation and 

 fertilizing will be amply repaid by the increased health of the trees, 

 and their resistance to attack by fungi or to unfavorable growth 

 conditions, when set in the grove. 



A point deserving the greatest attention, although not directly 

 related to the subject in hand, is the improvement of the industry 

 by bud selection. Of late years considerable attention has been given 

 to this phase of the work in California, and its value has been fully 

 demonstrated by the studies of Dr. Shamel, of the United States 

 Department of Agriculture. Briefly, this work consists in obtaining 

 "tree-performance" records over a period of years (that is, the 

 actual production as well as the character of the fruit of each tree) 

 and then using for propagating material, buds from those trees that 

 have given the highest yield of the desirable grade of fruit. This 

 subject is discussed in detail in Farmer's Bulletin No. 794, which 

 is distributed free by the United States Department of Agriculture, 

 and will well repay a careful perusal. 



As the woi'k with citrus diseases progresses attention will be given 

 to the possibility of checking certain of them by using buds from 



