califoe:n^ia experiments on western yellow pine. 



17 



WEATHER CONDITIOXS. 



Table 10 shows the weather conditions 



during 



the 



CaUfornia 



experiments, inchiding three months preceding and one month 

 following. The mean temperature on the area from June 1 to 

 November 30 was a few degrees lower than the mean temperature 

 recorded for the Florida ^ experiments from March 17 to November 2. 

 The diurnal range is much greater than in Florida. The total ramfall 

 on the California area for the period of the experiments amounted 

 to only 2.16 inches. 



Table 10.— Meteorological record, N'orthfork (California) ranger station, 1911. 





Temperature. 



Precipitation. 



Month. 



Mean. 



Maximum. 



Minimum. 



Average 

 range 

 during 



24 hours. 



Rain. 



Snow. 





°F. 

 50.1 

 50.2 

 56.3 

 66.8 

 79.5 

 72.5 

 63.7 

 61.2 

 54.0 

 41.5 



°F. 

 84 

 79 



87 



103 



108 



101 



98 



94 



90 



76 



°F. 

 30 

 30 

 32 

 46 

 52 

 50 

 42 

 32 

 24 

 15 



°F. 

 25 

 29 

 34 

 37 

 39 

 39 

 39 

 43 

 45 

 29 



Inches. 



12.44 



4.25 



1.18 



Trace. 











.35 



.3 



1.51 



1.58 



Inch. 







April 







May 













July 







August 













October 







November . ... 







December 











yields. 



Table 11 shows the weights of gum secured from the area at the 

 various dippings. The average yield of 0.281 pound per cup per 

 week is slightly greater than that in the Florida experiments (0.263 

 pound; see p. 9), but it should be kept in mind that the California 

 experiments were not begun until July and that had they been started 

 earlier in the season this average might have been lower. Seventeen 

 faces were chipped at montlily intervals during December, January, 

 and Februar}^. A yield of 16 pounds of dip was obtained, which 

 shows that gum continues to flow throughout the winter. 



Table ] 1.^ — Weight of dip obtained from ivestern yellow pine in California {968 cups). 



July 18. . 

 July 18.. 

 Aug. 16. 

 Sept. 5.. 

 Sept. 15 . 

 Sept. 27. 



Date of dipping. 



Weight 

 of dip. 



Pounds. 

 630 

 384 

 702 

 610 

 418 

 554 



Date of dipping. 



Oct. 19 



Pounds. 

 578 



Nov. 1 



490 



Total 





4,366 



Average per cup per week 



0.281 



Weight 

 of dip. 



1 Forest Service Bulletin 40, A New Method of Turpentine Orcharding, by Charles H. Herty. 



