BULLETIN 231] WALNUT CULTURE IN CALIFORNIA. 303 



is influenced largely by the actual weight of the meat and shell; some 

 varieties have a good meat, but also a heavy shell, while others may 

 have no more or even less meat per nut, but a rather lighter shell, giv- 

 ing a higher percentage to a variety with less meat. Eureka and Neff, 

 for instance, have 47 per cent meat against 50 per cent or more in 

 Placentia. The two former varieties, however, average only 32 nuts to 

 the pound, while with Placentia it takes an average of 43 to make a 

 pound. In other words, in one average Eureka nut there is about 7 

 grams of meat, while in a Placentia nut there is only 5.4 grams, 

 although the two nuts are of nearly equal size. Varieties like Eureka, 

 Neff and El Monte have heavy shells, as well as heavy meats, and the 

 same is true to a considerable extent with Chase, Franquette and Pro- 

 lific. This condition is indicated by the high specific gravity of these 

 varieties. 



An instructive comparison is afforded by the figures given at the 

 end of the table for Seedlings No. 1 and No. 2. These nuts average 

 exactly the same size, both in volume and dimensions, but No. 1 is 

 considerably heavier than No. 2, the number of nuts per pound being 

 respectively 35 and 41. No. 1 is a nut of exceptional weight both of 

 meat and shell, being of only medium size, yet one of the heaviest 

 varieties in the list and at the same time having 50 per cent meat. Its 

 specific gravity, 72, is the highest of any nut which we have tested, yet 

 it is a soft shell and easily cracked in the fingers, though well sealed. 

 Seedling No. 2, of the same size but lighter weight than No. 1, is a nut 

 of exceptionally heavy meat ( 55 per cent) and very light, weak shell. 

 On the latter account it is probably worthless, commercially, although 

 of such exceptionally good meat. 



Specific Gravity. This figure is obtained by dividing the weight in 

 grams by the volume in cubic centimeters. This represents the com- 

 parative weight of nuts of the same volume or size in the different vari- 

 eties. For instance, with Chase and Placentia, which are practically 

 of the same size, the weight of sacks of nuts of equal size would be as 

 63 to 57 in favor of Chase, while the number of nuts would be the same. 

 Chase and Concord having the same specific gravity, 63, would weigh 

 alike in sacks of the same size, but it would take more Concord than 

 Chase nuts to fill the sack in the proportion of 19 to 17.5. Comparing 

 the Eureka and San Jose, sacks of equal size would weigh 66 pounds 

 of Eureka to every 44.5 pounds of San Jose, while at the same time 

 there would be more Eureka nuts in the sack in the proportion of 25 

 to 22. Comparing Eureka with Franquette, the weights of sacks of 

 equal size would be as 66 to 60, with the size of the nuts and, there- 

 fore, the number of nuts per sack about the same. The most desirable 

 qualities are high specific gravity, fairly large size, small number per 

 pound and high percentage of meat. 



