61 



CHAPTER XI. 



YIELD AND VALUE. 



Decandolle states the quantity of oil produced by 

 the Olive at fiftv per cent, of the gross weight : Sieuve 

 tells us that 100 lbs. Olives yield 32 lbs. of oil, viz. :— 21 

 from the pericarp, 4 from the kernel, and 7 from the 

 shell, while others state it at 25 per cent. ; and while 

 from an inferior variety the yield is set down as low as 

 10 per cent. 



Calculating the yield per tree, it is extremely diffi- 

 cult to give an average. In the case of the Olive as 

 with many other vegetable products, no rule can be 

 laid down. Its productiveness is governed by variety, 

 climate, soil, culture, and age. 



The quantity of the crop is also liable to be affected 

 by extremes of wet or drought, lateness of season, hail- 

 storms, gales of wind, and seasons unusually rife with 

 destructive insects. As in the case, therefore, of many 

 other crops, it is more safe to base your calculations, 

 whether of maximum or minimum, upon an average of 

 years ; but after allowing for all possible drawbacks, in 

 Olive countries, the tree is considered to be one of the 

 most profitable crops known to agriculture. 



In most of the statements given I find some point 

 of weakness which destroys their value as a guide. 

 Where the average per acre is given, the age of the 

 plantation is omitted ; while from the produce of single 

 trees in exceptional circumstances little can be learned. 

 The lowest average that I find is 1 gallon per tree ; 

 while on other estates the average is given at from 1J 

 to 2 gallons per tree. The yield of individual trees is 

 given at from 12 to 20 gallons ; while one tree of 

 renown is stated to have yielded as much as 55 gallons, 

 and another three hundredweight of oil, 



