LEGEND 
CURVES 
——_-_ STANDARD “C'SITES AVERAGES FOR ZZ, IT & IV. 
QUALITIES "GOOD" AND'POOR" HUBBARD CO.MINN.(FROM TABLE 9) 
CASS LAKE, MINN. (FROM TABLE 2.) 
CRAWFORD AND ROSCOMMON COUNTIES, MICH/GAN.(FROM TABLE 4.) 
——-- WESTERN ONTARIO (FROM TABLE 7.) 
20 
PLOTS 
. MUEBARD COUNTY GOOD’ ACCORDING TO CUBIC VOLUME (FROM TABLE 34) 
A HUBBARD COUNTY “POOR'ACCORDING TO CUBIC VOLUME (FROM TABLE 35) 
{0} ADAMS COUNTY, WIS.(FROM TABLE 12 ) 
x COX'S NORTHERN MINNESOTA PLOTS (FROM TABLE 11) 
40 50 60 ~ 70 60 30 701 
Fie. 3.—Jack pine age-height data and curves plotted with reference to Prof. Roth’s plan for site classification standard C. Shows average height ofdominant trees in stands of different ages. 
140205°—20—Bull. 820. To face page 16, 
{¢} 
