28 BULLETIN 820, U. S. DEPARTMENT OF AGRICULTURE. 
TABLE 16.—Cost per acre of growing jack pine, figured for $2, $5, and $8 initial invest- 
ment, including cost of land and cost of planting, if any, at compound interest. 
AT 6 PER CENT COMPOUND INTEREST. 
Cost per acre, at 6 per cent com- Cost per acre, at 3 per cent com- 
pound interest, pound interest. 
Age. : 
$2 $5 $8 $2. $5 $8 
Years 
20) Ee NG ree NM ales yee ete $8. 98 $19. 72 20. 44 $5.49 $11.7 $17.94 
Ls yarioie APR a toe St eee Alba or a Se 12.42 26.95 41.47 6.74 14.12 21.49 
3 Opsiiee ey rae oe oe a Ore koran 17.02 36. 63 56. 23 8.18 16.90 25.60 
bop Si Ss op ates Aw ee ey See een a 23.17 49.57 75.98 9.86 20.12 30.37 
AQ) Boe etreaeTer Rese a eerste rare IR 31. 40 66.91 102. 41 11.80 23.85 25.90 
ZOE ae ee Ohi e eA Seen CU a AIE pec 42, 42 90. 09 137.78 14.05 28.18 42.30 
BO een ie ROSIE A aD sip aan rade 57.16 121.13 185.10 16.67 33.20 49.73 
Li Gi ane pale eenetet ey CA eet a 76. 89 162. 67 248. 45 19.69 39.02 58.35 
COS See alee mene Lee 103.3 218. 2 333. 22 23.19 45.77 68.33 
G5 ee EN On ee 138. 63 292. 64 446.65 27.26 53.58 79.90 
Oe nae LU ees A ie ete eae 185. 91 592.19 598. 45 31.98 62.65 93.32 
The following is allowed for annual expenses in the above calculations: Five cents per acre for admin- 
istration and protection, plus 1 per cent of initial cost for taxes, at 6 per cent or 3 per cent compound interest. 
This amount is added to the cost of the initial investment to date. 
MANAGEMENT. 
SUITABILITY OF JACK PINE FOR MANAGEMENT. 
Jack pine is well suited for forest management for three reasons: 
(1) It thrives on poor soils; (2) it quickly reproduces itself after 
lumbering and fire, forming pure, densely stocked stands; and (3) 
it grows rapidly in its early years and soon attains sizes suitable for 
pulpwood, box boards, crating, small-dimension lumber, mine tim- 
bers, and slack-cooperage staves and heading. Its good growth on 
poor soils, unsuited to agricultural crops or on which more valuable 
kinds of tress do not readily seed up, suggests the possibility of 
utilizing large tracts of land which would otherwise be unproductive. 
The probability of this class of lands coming more and more under 
State or Federal control increases the importance of jack -pine as a 
tree for forest management on a large scale. 
Jack pine quickly seeds up poor soils and burned-over areas and 
makes them productive much sooner than would otherwise be the 
case. The more valuable Norway and white pines gradually seed 
in under the shelter of jack pine stands when the soil conditions im- 
prove. Wherever there is Norway or white pine reproduction 
underneath it to take its place, the jack pine should be eliminated 
after it reaches merchantable size. 
Where jack pine occurs in mixture with Norway pine or other more 
valuable species on soils well suited to these latter, the natural 
reduction of jack pine that takes place with the increasing age of 
the stand should be allowed to go on. In some cases it may be 
advisable to reduce the proportion of jack pine by one or more 
cuttings to encourage the more valuable Norway pine in restocking 
the area and afterward to supplement the natural reproduction with 
