6 



BULLETIN 815, TJ. S. DEPARTMENT OF AGRICULTUEE. 



an entire year had been obtained, it was transferred to a form having 

 sufficient space for assembling the data of the individual tree for a 

 period of several years. These performance-record forms, together 

 with a more detailed account of the methods of compiling the rec- 

 ords, are shown in United States Department of Agriculture Bulletin 

 813, entitled "Citrus-Fruit Improvement: A Study of Bud Variation 

 in the Eureka Lemon." 



DESCRIPTIONS OF THE IMPORTANT STRAINS. 



LISBON STRAIN. 



The Lisbon strain was originally called the Semidense Productive 

 strain, on account of its habit of growth and productiveness. From 

 the fact that the habit of growth of the trees and the characteristics 

 of the fruits of this strain most nearly resemble the established ideal 



Fig. 1.— a typical lemon tree of the Lisbon strain (25 years old), No. 1-28-14 in the performance-record 

 plat, showing the dense appearance of the foliage. The summarized record of this tree is presented in 

 rank 23 in Table I. 



for the Lisbon variety, it has been decided to call it the Lisbon strain. 

 The trees of this strain are more productive than those of any other 

 strain of the variety. The bulk of the crop reaches the necessary 

 size for picking during the winter and spring seasons. 



The habit of growth of the trees is spreading, as shown in figure 1, 

 and more or less upright. The fruits are largely borne on the inside 

 of the tree and are protected from climatic injuries by the covering of 

 rather dense dark-green leaves. The leaves are of medium size, 

 oval in shape, obtuse, sHghtly crenate, abundant, and from deep to 

 dark green in color. The flowers are usually perfect. 



