AKIZONA EXPERIMENTS ON WESTERN YELLOW PINE. 



11 



Area A produced considerably more scrape than areas B or C. 

 This is accounted for in part by the fact that about one-tliird of the 

 faces on A were worked for six weeks in the preceding year (1910). 



COMPARISON OF YIELDS OF DIP AND SCRAPE FROM BLACK JACK AND YELLOW PINE. 



The ^delds of dip and scrape from both black jack and yellow pine 

 are shown in Table 6: 



Table 6. — Weight of dip and scrape obtained from black jach and yellow pine. 



BLACK JACK. 





Number 

 of cups. 



Weight of dip. 



Weight of scrape. 



Area. 



Total. 



Per cup 

 per week. 



Total. 



Per face. 



A 



175 

 140 

 332 



Founds. 



1,063.5 



754.0 



1,535.0 



Pound. 



0.253 



.224 



.193 



Pounds. 

 211.50 

 89.75 

 192.00 



Pounds. 

 1.21 



B 



.641 



c 



.578 







All areas 



647 



3,352.5 



.216 



493.25 



762 







YELLOW PINE. 



A 



325 

 360 

 168 



1.799.00 



1,770.25 



896.75 



0.231 

 .205 

 .222 



312.25 

 225.00 

 96.25 



0.961 



B 



.625 



c 



,573 









853 



4,466.00 



.218 



633.50 



.742 







On areas A and B the black jacks gave a larger flow per cup than 

 the yellow pines, wliile on C this was reversed. But including all 

 trees of both classes the average yield per cup was practically the 

 same. The production of scrape on area A was considerably larger 

 per face for black jack than for yellow pine; on B and C the produc- 

 tion per face was about the same for both classes of timber; taking 

 all areas, therefore, the production of scrape ran slightly higher for 

 black jack than for yellow pine. 



COMPOSITION OF DIP. 



The results of 22 analyses of samples of crude gum are shown in 

 Table 7. These analyses show only the proportions of volatile oil, 

 rosin, water, and chips in the crude gum. Ordinary turpentine from 

 the southern yellow pines consists almost entirely of pinene. A 

 further analysis ^ of the volatile oil from gum obtained in Arizona 

 shows it to be mostly pinene with a small proportion of a higher 

 boiling terpene not found in ordinary turpentine. There is no appar- 

 ent reason why Arizona turpentine can not be used commercially with 

 entire satisfaction. The same is true of the Arizona rosin. 



1 Forest Service Bulletin 119, An Examination of the Oleoresins of Some Western Pines, by A, 

 Schorger. 



W. 



