BULLETIN 231] WALNUT CULTURE IN CALIFORNIA. 157 



cent hybrids, and seedlings from certain trees will some years run above 

 90 per cent. 



We have observed Paradox trees resulting from the following crosses : 



English x Northern California Black. 



English x Southern California Black. 



English x Juglans nigra. 



English x Juglans major. 



Also English x Paradox and English x Royal. 



Trees of the first cross mentioned are found very commonly in certain 

 nurseries where the northern California species has been planted. Also 

 many trees grow in the northern part of the State among those which 

 have been planted for northern California black and also those which 

 have been planted for English. The so-called Smith tree near Elk Grove 

 is an example of the latter. This particular tree bears a much larger nut 

 than most Paradox walnuts. There are few trees of the cross in this 

 direction in the State, simply from the fact that very few seedling walnut 

 groves have been planted in the northern part of California. 



Paradox trees grown from northern black nuts are very common. 

 Most notable is that called the Yuba City tree, which stands in the town 

 of the above name just across the street to the north of the court house. 

 This tree is undoubtedly the largest walnut tree in California, and, in all 

 probability, the largest in the world. Its great size is accounted for by 

 its age, as it appears to have been planted at least forty years ago along 

 with several neighboring ordinary black walnuts of the northern Cali- 

 fornia type. Any one interested in walnuts will be well repaid by a visit 

 to Yuba City for the purpose of seeing this grand tree. It is conspicuous 

 long before reaching the town, rearing its enormous head above every 

 other object in the whole vicinity. The tree bears a considerable quan- 

 tity of nuts every year, but the amount of the crop is insignificant in 

 proportion to the size of the tree. 



Other Paradox trees occur in almost all the northern California towns 

 and may be distinguished by their great rapidity of growth, very thrifty 

 and vigorous appearance, foliage and general aspect closely resembling 

 that of the English walnut, and very light production of inferior, very 

 hard-shelled nuts. 



Paradox trees resulting from the cross between the English and the 

 southern California black are quite frequent in the south. In this case 

 almost all the older trees resulted from the planting of the English 

 walnut, as very few of the southern California black walnuts have ever 

 been planted except in nurseries. In the latter case hybrids coming 

 from the nuts of the black walnut are very common. In many of the 

 seedling walnut orchards of the southern part of the State hybrids of the 

 English and southern black have occurred. Frequently several trees of 



