18 Farmers' Bulletin 1096. 



bee. It is well known that bees will often not work on even moder- 

 ately cool days; if the afternoon temperature is below a certain 

 point, namely about 60 F, the bees may remain in the hive. On 

 days following the occurrence of a frost heavy enough to make 

 smudge protection necessary the temperature is likely to be suf- 

 ficiently low to keep the bees from working to any great extent. 

 On warm sunshiny days following heavy frosts, however, the writer 

 has often observed great numbers of bees working in blossoms that 

 had been heavily smudged on the previous night. 



The smoke from the open heaters is very dense and in some locali- 

 ties the residents of towns have objected to orchard heating on 

 account of the resulting dirt. The smoke problem has been partially 

 solved by the development of improved heaters, but no practical 

 heater has yet been devised that will burn under orchard condi- 

 tions without giving off some smoke. The newer types are rather 

 complicated and are" too expensive to be used for the protection 

 of crops that do not bring a large return. *fhere are few com- 

 mercial fruit districts in the country that do not suffer severely 

 from frost damage at intervals, and in most localities people are 

 willing to put up with some inconvenience from smoke on a few 

 nights a year in order to avoid the business depression likely to 

 follow the loss of a large portion of the crop. 



Protection of Olives. In some parts of California the olive crop 

 is often damaged severely by fall frosts when the fruit is being 

 picked. In some olive-growing communities as much as TO per cent 

 of the crop has been lost in some seasons in this manner. Many 

 growers have hesitated to resort to orchard heating to save the 

 crop for fear that the oil smoke would affect the flavor of the 

 olives. Mr. F. Mier, of Fair Oaks, Calif., has been protecting his 

 olives with open oil heaters for several years and has never been 

 able to note any effect on the flavor of the fruit. Practically his 

 entire crop has been packed ripe and has always been of the highest 

 quality. It is unlikely that the oil flavor ever penetrates the thick, 

 tough skin of the olive, but even if this were possible, the treat- 

 ment with lye which the fruit is given to remove the bitter ele- 

 ment would undoubtedly remove it. 



Relative Value of Different Fuels. The kind of fuel most suitable 

 for use in a given locality depends on a number of factors. The firsf 

 consideration is the relative cost of the different fuels. On the 

 Pacific coast oil is used almost exclusively on account of its low 

 cost as compared with coal or w r ood. In most other parts of the 

 country coal is the cheaper fuel. The acreage protected by wood 

 fires is relatively small. Because of the ease with which it may be 

 lighted and extinguished, handled and stored, oil is to be preferred 

 when its cost compares favorably with that of other fuels. 



