SUGAE PINE. 25 



Table 15. — Height growth of saplings and poles in the Sierra Nevada Mountains. 





Sugar 



Yellow 





Sugar 



Yellow 



Age. 



pme 



pme 



Age. 



pme 



pme 



total 



total 



total 



total 





height. 



height. 





height. 



height. 



Years. 



Feet. 



Feet. 



Years. 



Feet. 



Feet. 



10 



4 



12 



40 



62 



69 



20 



19 



34 



40 



73 



82 



30 



45 



52 



00 



82 



91 



Height measurements of over 700 seedlings and saplings taken on 

 virgin forest areas show the average height of young sugar pines 

 gro\vn imder such conditions to be only about 5 feet at the end of 40 

 years. The above table indicates a height of 62 feet at this age. This 

 startling difference shows that the tree responds quickly to- proper 

 conditions of light, soil, and moisture, and is an encouraging indica- 

 tion of what may be accomplished by proper management. 



In order to show the height growth of trees over 60 years of age, 

 287 trees were measured in four representative locahties in the virgin 

 forests of the Sierra Nevada Mountains. Table 16 shows the rates of 

 height growth in the best and poorest situations and also the average 

 growth on all plots. 



Table 16. — Maximum, minimum, and average heights based on age in virgin California 

 forests {Sierra Nevada Mountains). 



Age. 



Total height. 



Maxi- 

 mum 

 current 

 annual 

 growth. 



Age. 



Total height. 



Maxi- 

 mum 

 current 

 annual 

 grcvth. 



Maxi- 

 mum. 



Average. 



Mini- 

 mum. 



Maxi- 

 mum. 



Average. 



Mini- 

 mum. 



Years. 

 20 

 40 

 60 

 80 

 100 

 120 

 140 

 160 

 180 

 200 

 1 



Feet. 

 8 

 24 

 49 

 K4 

 111 

 127' 

 139 

 148 

 157 

 165 



Feet. 



Feel. 



Feet. 



0.40 



.80 



1.25 



1.75 



1.35 



.SO 



.60 



.45 



.45 



.40 



Years. 

 220 

 210 

 260 

 280 

 300 

 320 

 340 

 360 

 380 

 400 



Feet. 

 173 

 180 

 187 

 194 

 200 

 206 

 212 

 218 



Feet. 

 148 

 153 

 158 

 162 

 167 

 171 

 174 

 177 

 180 

 183 



Feet. 

 127 

 129 

 131 

 132 

 134 

 135 

 13G 

 137 



Feet. 



0.40 

 .35 

 .35 

 .35 

 .30 

 .30 

 .30 

 .30 



23 

 45 

 72 

 92 

 106 

 118 

 127 

 135 

 142 







ei 



77 

 91 

 103 

 112 

 119 

 124 















It is evident that tjic period of most rapid growth is from the 

 eightieth to the hundredth year of life in the best locahties, at which 

 time the annual increase in height amounts to 1.75 feet. At the ago 

 of about 110 years the rate of height growth Jias fallen off to such an 

 extent that current annual growth is less than the mean annual 

 growth or average annual growth for the entire growhig life of the 

 tree. 



MERCHANTABLE AND CLEAK LENGTHS. 



From a comriuTfial standpoint the merchantable lengt]i of a, species 

 (the Icjigdi of tliat s<;ction of tlie tree wJiich can be utilized ajid the 

 chuir Icnglli free from limbs and yielding higli-gradc lumber) is more 



