JACK PINE. 29 
a planting of Norway pine. Similarly, it will often be advisable to 
plant Norway or white pine on vacant areas where the soil is suitable, 
which otherwise might become seeded up to jack pine by natural 
reproduction, as is being done in parts of Michigan. On poorer soils, 
however, where Norway or white pine has a poor chance of success, 
natural jack pine reproduction should always be encouraged. 
The possible returns in growing jack pine may be estimated from 
Table 15, which gives the stumpage value per acre at different ages, 
ficured for different values per cord and per 1,000 board feet, taken 
in connection with Table 16, which gives the cost per acre of growing 
such stands. Thus, on “good” quality jack pine land the stumpage 
value per acre of a 40-year-old stand at $1 per cord amounts to $28, 
as shown by Table 15. Reference to Table 16 shows that in 40 years, 
with money at 6 per cent and with an original investment of only $2 
per acre, at which cost it would very rarely be possible to secure 
adequately stocked stands, the cost would be $31.40, or $3.40 more 
than the stumpage value. On the other hand, money at 3 per cent 
would admit of an original cost of $8 per acre and give a profit of 
$2.10 per acre above the 3 per cent interest earned on all money 
invested. In general, raising jack pine is at present a losing invest- 
ment as compared with other investments at 6 per cent, but a 
very good one as compared with others at 3 per cent. At this 
latter rate of interest the State or Federal government would be 
fully justified in growing it on lands unsuited to agricultural crops 
or to more valuable species of trees. 
ROTATION. 
A short rotation for jack pine is the most practicable for securing 
the best financial returns and the reproduction of a new stand with 
the least difficulty. A comparison of Tables 14 and 15 indicates the 
financial advisability of a short rotation. Thus, with a stumpage 
value of $5 per 1,000 board feet mill scale, and with $5 original 
investment at 6 per cent on ‘‘good”’ quality of jack pine land, the 
best financial rotation appears to be around 35 years. When trees 
are of this age the stumpage value would be $52.50 per acre, and 
the cost, at 6 per cent interest on all money invested, only $49.57. 
On lands under public control, where the financial return is sec- 
ondary to the object of making otherwise waste land productive, a 
rotation of 60 years may be advisable, which would allow the pro- 
duction of ties and lumber as well as mine timbers, box boards, and 
pulpwood. 
PROTECTION. 
Since fires, even if not severe enough to kill the trees outright, 
practically always damage stands by impoverishing the soil, injuring 
and weakening individual trees, and reducing their resistance to 
