126 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. 



orchard form. 1 If walnut trees could be obtained which would average 

 200 pounds of good nuts per tree in the orchard, the profits from such 

 a planting would probably equal the average returns from citrus groves, 

 while 300 pound trees would be even better than the latter in the long 

 run. Since such trees already exist in individual cases, there is no 

 reason to doubt that it may ultimately be possible to produce commer- 

 cial orchards of this sort. 



During the many years during which the walnut has been under 

 domestication, both in the old world and the new, it has, like all other 

 cultivated plants, come to vary to a large extent in individual trees 

 in regard to the characteristics of the tree, and particularly in regard 

 to the size, form, flavor and other qualities of its fruit. Likewise, as 

 with other crops, certain individuals of superior merit of one sort or 

 another have been noted from time to time, and many such individ- 

 uals have been given definite names as special varieties and the 

 peculiar properties of these varieties have been perpetuated by bud- 

 ding or grafting. In this way we have many definite varieties of the 

 walnut, just as with the apple, peach and other fruits. In a broader 

 way, the walnut has also become broken up into certain more or less 

 well-defined types, which come true to a certain extent from seed. 



OTHER SPECIES OF WALNUT. 



A considerable number of walnut species is found in various portions 

 of the world, in addition to the cultivated form, Juglans regia. "Jug- 

 lans is now confined to the temperate and southern parts of North 

 America, the Antilles, South America from Venezuela to Peru, the 

 Caucasus, Persia and northwestern India, Manchuria, northern China, 

 and Japan. About ten species are known; two are widely distributed 

 in the forests of eastern North America; one inhabits western Texas, 

 New Mexico, and Arizona, ranging far south into Mexico, where one 

 and perhaps two other species occur; and one inhabits the valleys of 

 western California. The flora of the Antilles contains a single species 

 of Juglans, while two or perhaps three others occur in the northern 

 and western countries of South America. In the old world the genus 

 is represented by Juglans regia, an inhabitant of southeastern Europe 

 and western Asia and now cultivated in all temperate countries, by 

 Juglans mandshurica of the Amur valley and northern China, and 

 by Juglans sieboldiana of Japan."* 



J The famous Payne tree, near San Jos6, has produced over 700 pounds of nuts in 

 one year, but this is a large black walnut tree, topworked in the branches. 

 * Sargent, Silva of North America. 



